Surface light emitting devices

ABSTRACT

It is an object of the present invention to provide a surface light-emitting device that can realize a lightweight and compact-profile optical input/output device with reasonable price, especially the one that emits light. The beam generator  12  comprises a surface light-emitting device having a stacked-layer formed of a cathode  2,  a luminescent layer  4  made of organic material(s) and an anode  6  in that order, the stacked-layer being located adjacent to a glass substrate  8.  The anode  6  is a transparent electrode that is formed to correspond to a hologram pattern of a condensing lens. When a DC voltage is applied between the cathode  2  and the anode  6  with the DC power source, the luminescent layer  4  illuminate corresponding to the hologram pattern of the condensing lens, and the light will converge to a focal point of the condensing lens. Therefore, the surface light-emitting device can play the both roles of the light source and the condensing lens. Thus, the use of this surface light-emitting device permits realization of a lightweight and compact-profile beam generator with reasonable price.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] All the contents disclosed in Japanese Patent Application No.H10-296659 (filed on Oct. 19, 1998), No. H10-296663 (filed on Oct. 19,1998), No. H10-313221 (filed on Nov. 4, 1998), No. H10-313226 (filed onNov. 4, 1998), No. H10-313228 (filed on Nov. 4, 1998), No. H10-322981(filed on Nov. 13, 1998), No. H10-347281 (filed on Dec. 7, 1998), andNo. H10-347287 (filed on Dec. 7, 1998) including specification, claims,drawings and abstract and summary is incorporated herein by reference inits entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to surface light-emitting devices,more specifically to a surface light-emitting device capable of usingfor an optical-input/output device and an image display device includinga surface light-emitting device.

[0004] 2. Description of the Related Art

[0005] Various devices for inputting/outputting light are known aslight-input/output devices. In the light-input/output devices, both ofbeam generators such as flashlights, turn-signals used for an vehicle,optical pointers using laser beams and beam output part and the like ina laser printer, and image display devices and so on displaying visualinformation including images and characters in fixed manner and/or indynamic manner, are used as devices for outputting light.

[0006] On the contrary, both of an optical pickup device and a bar-codereader and so on are used as a device for outputting light therefrom andinputting reflected light therethrough among the light-input/outputdevices. The optical pickup device and the bar-code reader may also beused as the beam generator because these include a beam output part.

[0007] Details of such light-input/output devices will be describedhereunder by using an optical pickup device as an example. The opticalpickup device is a device for reading out information recorded on acompact disc (hereinafter referred to as CD) and the like.

[0008]FIG. 41 is a conceptual view for describing a prior art opticalpickup device PU. The optical pickup device PU comprises a laser diodeLD, a half-mirror HM, a lens L, coils FC for carrying out auto-focus, aphoto-detector S, and a control circuit CT.

[0009] A laser beams emitted from the laser diode LD and pass throughthe half-mirror HM reaches to the recording layer (not shown) of the CDafter focusing with the lens L. Both the laser diode LD and the lens Lform the beam output part. The light reflected by the recording layer isfocused again with the lens L, and a part of the light reaches to thephoto-detector S as a result of reflecting with the half-mirror IM. Thedata recorded on the recording layer are read out with thephoto-detector S by detecting the amount of light detected thereby. Thefocal point of the laser beam can automatically be located on therecording layer of the CD by moving the lens L in a direction of X shownin the drawing with the coils FC.

[0010] The control circuit CT controls operations of all the laser diodeLD, the coils FC and the photo-detector S according to a command fromthe outside while outputting the data read out thereby.

[0011] The conventional optical pickup device, however, has thefollowing problems to be solved. The beam output part in the opticalpickup device PU requires the lens L for focusing the laser beams inaddition to the laser diode LD acting as the light source inconsideration of such part. In order to carry out a proper focusing,positioning between the laser diode LD and the lens L need to beperformed. Accordingly, it is difficult to make the beam output partsmaller in size, and the manufacturing cost thereof may also beincreased rapidly in accordance with its size.

[0012]FIG. 42 is a conceptual view for describing another prior artoptical pickup device PU. The pickup device PU depicted in FIG. 42includes a laser diode LD, a half-mirror HM, a lens L, a photo-detectorS, and a control circuit CT.

[0013] A laser beams emitted from the laser diode LD and pass throughthe half-mirror HM reaches on the recording layer (not shown) of the CDafter focusing by the lens L. Both the laser diode LD and the lens Lform the beam output part. Light reflected by the recording layer isfocused again with the lens L, and a part of the light reaches to thephoto-detector S as a result of reflecting with the half-mirror HM. Thedata recorded on the recording layer are read out with thephoto-detector S by detecting the amount of light detected thereby.

[0014] The control circuit CT controls operations of all the laser diodeLD, the coils FC and the photo-detector S according to a command fromthe outside while outputting the data read out thereby.

[0015] The conventional optical pickup device, however, also has thefollowing problems to be solved. The optical pickup device PU requiresthe lens L for focusing the laser beams and the half-mirror acting as abeam-splitter in addition to the laser diode LD acting as the lightsource and the photo-detector S for detecting light because the pickupdevice PU outputs light to the outside thereof and receives reflectedlight thereby. In other words, the pickup device PU requires a lot ofcomponents. In order to carry out proper focusing, positioning amongthese components need to be performed. Accordingly, it is difficult tomake the pickup device PU smaller in size, and the manufacturing costthereof may also be increased rapidly in accordance with its size.

[0016]FIG. 43 is a conceptual view for describing a prior art laserprinter LP. Laser printers are used for printing images and/orcharacters on a printing paper and the like.

[0017] The laser printer LP comprises a laser diode LD, a collimatorlens CL, a polygon mirror (which has flat reflective surfaces around theperimeter) PM, a condensing lens L, and a photosensitive drum SD formedin a cylindrical shape. The surface of the drum SD is charged withelectrostatic, and a part of the electrostatic on the drum is eliminatedwhen light is directed on that part.

[0018] A laser beam emitted from the diode LD is collimated with thelens CL, and is reflected with the polygon mirror PM. Thereafter, thereflected beam reaches on the drum SD by focusing with the lens L. Thediode LD, the lens CL, the mirror PM, and the lens L form the beamoutput part described earlier.

[0019] A laser beam is repeatedly scanned on the drum SD along withscanning lines SL in a direction such as top to bottom in the drawingbecause the polygon mirror PM is in rotation of a R2 direction. The drumSD, on the contrary, is rotated in a R3 direction synchronistical withthe rotation of the polygon mirror PM as shown in the drawing. In thisway, the laser beam is scanned all over the surface of the drum SD. As aresult, the laser beam can be directed on predetermined areas of thedrum SD by blinking the laser beam at a proper timing. In other words,electrostatic on the predetermined areas of the drum SD can beeliminated.

[0020] This allows printing of images and/or characters on a paper andthe like by fixing images and/or characters after attracting toner onthe area corresponding to existence of electrostatic on the surface ofthe drum SD.

[0021] The prior art laser printer, however, has the followingdrawbacks. Various optical components are needed such as the lens CL forcollimating the beam, the polygon mirror PM for scanning the beam, andthe lens L for focusing the beam, in addition to the diode LD acting asthe light source in consideration of the beam output part in the printerLP. In order to carry out proper focusing, positioning among thesecomponents need to be conducted. Accordingly, it is hard to make theprinter LP smaller in size, and the manufacturing cost thereof may alsobe increased rapidly in accordance with its size.

[0022] Mechanical rotation of the polygon mirror PM suppresses itsrotation speed and decreases durability of the printer LP.

[0023] In addition to laser printers, image display devices fordisplaying visual information including images and characters in fixedmanner and/or in dynamic manner such as light-emitting diode display(LED) devices, liquid crystal display (LCD) devices, plasma displaydevices, fluorescent display devices, are known. FIG. 44 is a viewillustrating an image displayed on a screen D in one of suchconventional display devices. The transfer of information and/orpropagation thereof such as advertisement can be carried out through thescreen D.

[0024] However, -the prior art image display devices described abovehave the following disadvantages. In these display devices, imagesand/or characters are just displayed on the screen D itself. In otherwords, these visual informations can not be reproduced on the screen Din three-dimensional manner through the display devices. It is,therefore, cubic objects can not be displayed in three-dimensionalmanner, and images and/or characters can not be displayed in a mannersuch that these looks like coming up to the viewer. With the imagesand/or characters displayed on the screen under flat display manner, notmuch advertising impacts are expected.

[0025] On the other hand, a lightweight and compact-profiled imagedisplay device suitable for mobile and portable use of individual userswith a reasonable price is expected.

SUMMARY OF THE INVENTION

[0026] It is an object of the present invention to overcome theabove-mentioned problems and to provide a surface light-emitting deviceutilizing holograms which can realize a lightweight, compact-profile,and reasonable-price optical-input/output device capable of outputtinglight. It is another object of the present invention to provide asurface light-emitting device including a light source suitable forreproduction of holograms. It is another object of the present inventionto provide a surface light-emitting device comprising a hologram layersuitable for reproduction of holograms. It is far another object of thepresent invention to provide a surface light-emitting device including ahologram layer capable of forming easily.

[0027] Further, it is still another object of the present invention toovercome the above mentioned problems and to provide a surfacelight-emitting device capable of realizing a lightweight,compact-profile, and reasonable price optical input/output device,especially, the device outputs light while using the reflected light asincident light.

[0028] Still further, it is yet another object of the present inventionto overcome the above mentioned problems and to provide a surfacelight-emitting device capable of realizing a lightweight,compact-profile, and a reasonable price optical-input/output devicewhich especially outputs light, as well as a surface light-emittingdevice carrying out reproduction of holograms with certainty.

[0029] It is another object of the present invention to overcome theabove mentioned problems and to provide a surface light-emitting devicecapable of realizing a lightweight, compact-profiled, and reasonablepriced optical-input/output device which especially outputs light, yetenables high-speed operation with high-durability.

[0030] Further, its is far another object of the present invention toovercome the above mentioned problems and to provide a lightweight,compact-profile, and reasonable price image display device capable ofdisplaying visual information in three-dimensional manner.

[0031] In other words, it is the principal object of the presentinvention to provide a surface light-emitting device capable ofrealizing a lightweight, compact-profile, and reasonable-priceoptical-input/output device, and to provide an image display deviceincluding a lightweight, compact-profiled, and reasonable-priced surfacelight-emitting device.

[0032] In accordance with characteristics of the present invention,there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode, wherein theelectrode is substantially formed in a shape corresponding to a patternof interference fringes of a hologram.

[0033] Further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode,

[0034] wherein a shielding layer formed in a shape substantiallycorresponding to a pattern of interference fringes of a hologram isprovided at a position outside of the luminescent layer,

[0035] and wherein the light from the luminescent layer is emittedthrough the shielding layer.

[0036] Still further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode,

[0037] wherein an uneven transparent layer formed unevenly in thicknesscorresponding to a pattern of interference fringes, is disposed at aposition outside of the luminescent layer,

[0038] and wherein the light from the luminescent layer is emittedthrough the uneven transparent layer.

[0039] In accordance with characteristics of the present invention,there is provided a surface light-emitting device including aluminescent layer made of an organic material and an electrode, theluminescent layer emitting light as a result of applying a voltage tothe electrode and the light being emitted in a direction substantiallyperpendicular to the luminescent layer through a predetermined opticalpath as a laser beam after carrying out resonation of the emitted light,

[0040] wherein a hologram layer formed substantially corresponding tothe patterns of interference fringes of a hologram is formed as a layerone of related to light emission and provided on the predeterminedoptical path.

[0041] Further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0042] wherein a hologram layer formed substantially corresponding tothe patterns of interference fringes of a hologram is formed as a layerone of related to light emission and provided on the predeterminedoptical path,

[0043] and wherein the light from the luminescent layer directed toother than the predetermined optical path is emitted to a directionother than the predetermined optical path.

[0044] In accordance with characteristics of the present invention,there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0045] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0046] and wherein the light from the luminescent layer directed toother than the predetermined optical path is reflected and incorporatedwith another light from the luminescent layer directed to thepredetermined optical path so as to intensify a resulting light.

[0047] Further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0048] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0049] and wherein the light from the luminescent layer is resonated andemitted.

[0050] Still further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0051] wherein a hologram layer formed substantially corresponding tothe patterns of interference fringes of a hologram is formed as a layerone of related to light emission and provided on the predeterminedoptical path,

[0052] and wherein the hologram layer is formed alone with a partlocated periphery of interference fringes of the hologram.

[0053] In accordance with characteristics of the present invention,there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0054] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0055] and wherein the hologram layer includes a light-pattern and adark-pattern,

[0056] and wherein a width of the light-pattern is substantially formedin a range of a wavelength of the light or less than said range.

[0057] Further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0058] wherein a hologram layer formed substantially corresponding tothe pattern of the interference is formed as a layer one of related tolight emission

[0059] and provided on the predetermined optical path,

[0060] and wherein the hologram layer includes a light-pattern and adark-pattern,

[0061] and wherein the light-pattern is formed in a fixed width, andwherein information containing light intensity of the holograms isreproduced in accordance with brightness of a portion generating lightwhere corresponding to the light-pattern.

[0062] Still further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0063] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0064] and wherein the device is fabricated so that the light onceemitted through the optical path returns through the hologram layer as areflected light.

[0065] In accordance with characteristics of the present invention,there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0066] wherein a hologram layer formed substantially corresponding to apatterns of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0067] and wherein a plurality of element regions is included in thehologram layer,

[0068] and wherein brightness of portions corresponding to the elementregions is determined in accordance with the patterns of theinterference fringes,

[0069] and wherein the corresponding portions are controlled so as toturn into an illumination-state corresponding to the determinedbrightness substantially at the same time.

[0070] Further, in accordance with characteristics of the presentinvention, there is provided a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0071] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0072] and wherein more than one pattern of interference fringes isprepared and light corresponding to one of patterns selected is emittedthrough the predetermined optical path.

[0073] Still further, in accordance with characteristics of the presentinvention, there is provided an image display device having a surfacelight-emitting device including a luminescent layer and an electrode,the luminescent layer emitting light as a result of applying a voltageto the electrode and the light being emitted through a predeterminedoptical path,

[0074] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath, and wherein a predetermined holographic image is displayed withthe light from the luminescent layer.

[0075] Other objects and features of the present invention will be moreapparent to those skilled in the art on consideration of theaccompanying drawings and following specification wherein are disclosedseveral exemplary embodiments of the invention with the understandingthat such variations, modifications and elimination of parts may be madetherein as fall within the scope of the appended claims withoutdeparting from the spirit of the invention.

BRIEF DESCRITION OF THE DRAWINGS

[0076]FIG. 1 is a sectional view for describing the structure of a beamgenerator 12 according to an embodiment of the present invention;

[0077]FIGS. 2A through 2D are sectional views showing layer structuresof the surface light-emitting devices;

[0078]FIG. 3 is a sectional view showing a molecular alignment oforganic materials in a luminescent layer 4;

[0079]FIG. 4A is a graph illustrating a relationship between bothvoltages applied between a cathode 2 and an anode 6, and electriccurrent density flowing through the luminescent layer 4;

[0080]FIG. 4B is a graph illustrating a relationship between bothvoltages applied between the cathode 2 and the anode 6, and lightintensity of the luminescent layer 4;

[0081]FIGS. 5A through 5C are sectional views showing examples of thestructures of surface light-emitting devices applicable to the presentinvention;

[0082]FIGS. 6A and 6B are sectional views showing another examples ofthe structures of surface light-emitting devices applicable to thepresent invention;

[0083]FIG. 7 is a sectional view showing far another examples of thestructure of surface light-emitting device applicable to the presentinvention;

[0084]FIGS. 8A and 8B are sectional views showing still another examplesof the structures of surface light-emitting devices applicable to thepresent invention;

[0085]FIG. 9 is a sectional view for describing an embodiment of asurface light-emitting device realizing a light source much suitable forreproduction of holograms;

[0086]FIG. 10A is a sectional view showing the structure of embodimentof the surface light-emitting device realizing the light source muchsuitable for reproduction of holograms;

[0087]FIG. 10B is a graph illustrating the functions of said surfacelight-emitting device;

[0088]FIG. 11A is a sectional view showing the structure of anotherembodiment of the surface light-emitting device realizing the lightsource much suitable for reproduction of holograms;

[0089]FIG. 11B is a graph illustrating the functions of said surfacelight-emitting device;

[0090]FIGS. 12A and 12B are graphs illustrating the function of thesurface light-emitting device shown in FIG. 11A.

[0091]FIG. 13A is a sectional view showing the structure of stillanother embodiment of the surface light-emitting device realizing thelight source much suitable for reproduction of holograms;

[0092]FIG. 13B is a view illustrating the functions of said surfacelight-emitting device;

[0093]FIG. 14 is a sectional view for describing the structure of yetanother beam generator 40 according to another embodiment of the presentinvention;

[0094]FIG. 15 is a plan view illustrating typical planar structure ofhologram layers;

[0095]FIG. 16 is a view illustrating typical patterns of interferencefringes themselves corresponding to the hologram layers shown in FIG.15;

[0096]FIG. 17 is a view illustrating a typical condition in whichcollimated light is directed to ordinary transmission-type holograms HGin a direction of arrows extending from the left-hand side to theright-hand side in the drawing;

[0097]FIG. 18 is a sectional view for describing the structure of anoptical pickup device 50 in another embodiment of the present invention;

[0098]FIGS. 19A through 19C are sectional views showing another examplesof the structures of surface light-emitting devices applicable to thepresent invention;

[0099]FIG. 20 is a sectional view for describing the structure of faranother beam generator 60 according to another embodiment of the presentinvention;

[0100]FIG. 21 is a sectional view showing an example of the structure ofanother surface light-emitting device applicable to the presentinvention;

[0101]FIG. 22 is an exploded perspective view of the beam generator 60;

[0102]FIG. 23 is a circuit diagram showing part of a circuit in the beamgenerator 60;

[0103]FIG. 24 is a view for describing a series of operations to displayan alphabetical character “F” with the beam generator 60;

[0104]FIG. 25 is a sectional view for describing the structure ofanother beam generator 66 according to another embodiment of the presentinvention;

[0105]FIG. 26 is a view for describing the structure of a barcode reader70 according to another embodiment of the present invention;

[0106]FIG. 27 is a conceptual view for describing an example of a priorart barcode reader BR;

[0107]FIG. 28 is a sectional view for describing the structure ofanother beam generator 80 according to another embodiment of the presentinvention;

[0108]FIG. 29 is a view showing an example of a surface light-emittingdevice of another embodiment of the present invention;

[0109]FIGS. 30A and 30B are views illustrating patterns of hologramobtained by the surface light-emitting device shown in FIG. 29;

[0110]FIG. 31 is a sectional view for describing the structure of animage display device 90 according to another embodiment of the presentinvention;

[0111]FIG. 32 is a sectional view showing an example of the structure ofanother surface light-emitting devices applicable to the presentinvention;

[0112]FIG. 33 is a view showing appearance of an IC card 94, an exampleof applying the image display device 90;

[0113]FIG. 34 is a sectional view showing the overall structure of anexample of a surface-emitting laser device;

[0114]FIG. 35 is a view for describing the structure of another beamgenerator 100 according to far another embodiment of the presentinvention;

[0115]FIG. 36 is a plan view for describing the structure of the beamgenerator 100;

[0116]FIGS. 37A and 37B are sectional views for describing amanufacturing method of a surface light-emitting device composing thebeam generator 100;

[0117]FIGS. 38A and 38B are sectional views for describing themanufacturing method of the surface light-emitting device composing thebeam generator 100;

[0118]FIG. 39 is a view for describing the structure of another beamgenerator 130 according to another embodiment of the present invention;

[0119]FIG. 40 is a sectional view for describing the structure ofanother beam generator 140 according to another embodiment of thepresent invention;

[0120]FIG. 41 is a conceptual view for describing a prior art opticalpickup device PU;

[0121]FIG. 42 is a conceptual view for describing another prior artoptical pickup device PU;

[0122]FIG. 43 is a conceptual view for describing a prior art laserprinter LP;

[0123]FIG. 44 is a view illustrating an image displayed on a screen D inone of such prior art image display devices.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0124] Chapter 1

[0125]FIG. 1 is a sectional view for describing the structure of a beamgenerator 12 according to an embodiment of the present invention. Thebeam generator 12 comprises stacked-layers formed of a cathode 2 actingas an electrode layer, a luminescent layer 4 and an anode 6 forminganother electrode layer in that order, the stacked-layers being locatedadjacent to a glass substrate 8 forming a supporting body. A DC powersource 10 is connected between the cathode 2 and the anode 6. All thecomponents of the beam generator 12 except for the DC power source 10form a surface light-emitting device.

[0126] The anode 6 is a transparent electrode formed in a shape so as tosubstantially correspond to patterns of interference fringes ofholograms. In this embodiment, description of the present invention willbe made under an assumption in which the beam generator 12 is applied toan optical pickup device. It is also assumed that patterns of hologramsof a condensing lens forming an optical element are used as the patternsof interference fringes of holograms. In other words, arrangement ofportions 6 a, 6 b, 6, 6 d, and so on composing the anode 6 respectivelycorrespond to the patterns of interference fringes of holograms.

[0127] In order to fabricate a surface light-emitting device composingthe beam generator 12, the following steps need to be carried out. Alayer made of metal and the like (its details will be described later)which is used for forming the cathode 2 is formed on the surface of theglass substrate 8 by carrying out evaporation method or the like. On themetal layer thus formed, another layer made of organic materials (itsdetails will be described later) composing the luminescent layer 4 isformed with vacuum evaporation method and the similar method. Faranother layer made of transparent metal oxide electrode which is usedfor forming the anode 6 is formed on the organic layer by using a shadowmask under evaporation method and the like. Subsequently, the operationof the beam generator 12 will be described hereunder. The portions inthe luminescent layer 4, interposed between the cathode 2 and theportions 6 a, 6 b, 6 c, 6 d and so on composing the anode 6, emit lightwhen a DC voltage is applied between the cathode 2 and the anode 6. Asdescribed earlier, the portions 6 a, 6 b, 6 c, 6 d and so on composingthe anode 6, are located at positions correspondent to the patterns ofholograms of the condensing lens. In this way, the light emitted fromthe luminescent layer 4 is focused on a focal point of the condensinglens by traveling in a forward-direction (a direction in which a compactdisc CD and the like is allocated) and pass through these portions 6 a,6 b, 6 c, 6 d, and so on.

[0128] The compact disc CD is allocated at a position so that the focalpoint of the condensing lens is on the recording layer (not shown)thereof The data recorded on the recording layer are read out bydetecting the amount of light reflected thereby.

[0129] As described above, the anode 6 is formed in a shape so as tocorrespond substantially to the patterns of holograms of the condensinglens in this embodiment. In this way, a part of the luminescent layer 4emits light corresponding to the patterns of holograms of the condensinglens as a result of applying a voltage between the cathode 2 and theanode 6.

[0130] Consequently, this surface light-emitting device alone can playboth roles as the light source and the condensing lens. In other words,the beam generator 12 can be made as a lightweight, compact-profiled,yet reasonable priced device by using the surface light-emitting device.

[0131] As described earlier, the luminescent layer 4 composing a part ofthe surface light-emitting device is made of organic materials.Although, no specific limitation on the materials of the organicmaterials, for example electro-luminescent materials having a smallmolecule such as materials Et-DSB, BczVBi, DPVBi and so on ofdistyrylarylene, oxadiazole, pyrazoloquinolin, Zn (BOX) 2 ofbenzoxazole, BA lq 1 of aluminum chelate may be used. In addition,electro-luminescent materials having high molecular may also be used forthe luminescent layer 4.

[0132] The use of organic materials to the luminescent layer 4 permitsthe formation thereof with a very thin in thickness (in a range of 10nano-meters through 100 nano-meters) in comparison with wavelength ofthe emitted light therefrom. In this way, the active thickness of theportions emitting light in the luminescent layer 4 can be formed in athickness, which is negligible (about 5 nano-meters) in comparison withthe wavelength of the emitted light (a range of 400 nano-meters through700 nano-meters in visible light). In addition, the minimum planardimension of the luminescent layer 4 can dramatically be smaller (in arange of 10 nano-meters through 100 nano-meters) in comparison with thewavelength of the emitted light. It is, therefor, possible to provide aluminescent layer 4 suitable for reproduction of holograms by usingorganic materials therefor.

[0133] The use of organic materials further permits the luminescentlayer 4 to emit light at a low DC voltage.

[0134] Although, no specific limitation on the material of the anode 6,for example, transparent metal electrode such as indium tin oxide (ITO),indium oxide, zinc oxide and the like may be used for the anode 6. Othermetals having a large work function such as Au can also be used in viewof improving the efficiency of injection of positive holes.

[0135] Although, no specific limitation on the material of the cathode2, for example metals having a small work function such there is asgroups of Mg, Li, Ca can also be used in view of improving theefficiency of injection of electrons. It is further preferred to makealloys of different metals such as Mg:Ag, Mg:Al, Al:Li, to increase itsstabilization. Because such alloys become hard to be oxidized even wheneach of the metals has a small work function.

[0136] Although, the surface light-emitting device having a structuralfeature of in which the luminescent layer 4 is interposed between thecathode 2 and the anode 6, is described in the above, the structuralfeature thereof is not limited to that. Surface light-emitting deviceshaving structural features according to the present invention areexampled in FIGS. 2A through 2D. The structural feature described in theabove is shown in FIG. 2A.

[0137]FIG. 2B shows a structure in which a hole transport layer (HTL) 14is further interposed between the luminescent layer 4 and the anode 6shown in FIG. 2A.

[0138] Although, there is no specific limitation on the materials of thehole transport layer 14, materials having a high capability of holeinjection into the luminescent layer 4 while no injection of electronsthereto from the luminescent layer 4, is preferred therefor. A materialsmade of amin may be used therefor.

[0139]FIG. 2C shows a structure in which an electron transport layer(ETL) 16 is interposed between the cathode 2 and the luminescent layer 4shown in FIG. 2B.

[0140] Although, there is no specific limitation on the materials of theelectron transport layer 16, for example an aluminum chelate materialsuch as A lq and the like, or oxadiazole derivatives and the like mayalso be used therefor.

[0141]FIG. 2D shows a structure in which a hole injection layer 18 isinterposed between the hole transportation layer 14 and the anode 6shown in FIG. 2C.

[0142] Although, there is no specific limitation on the materials of thehole injection layer 18, materials having a low hole injection barrieragainst the anode 6 is preferred therefor. For instance, materials madeof amin or that of phthalocyanine may be used therefor.

[0143]FIG. 3 is a sectional view showing a molecular alignment of anorganic material in the luminescent layer 4. Although, no specificlimitation in the direction of molecular alignment of the organicmaterial in the light-emitting material 4, the molecular alignment in adirection substantially parallel to both the cathode 2 and the anode 6permits stronger light-emitting intensity even when a low voltage isapplied.

[0144]FIG. 4A is a graph illustrating a relationship between bothvoltages applied between the cathode 2 and the anode 6, and electriccurrent density flowing through the luminescent layer 4. In the graph,black dots indicate the relationship therebetween when the molecularalignment is in a direction substantially parallel to both the cathode 2and the anode 6, and white dots indicate the relationship therebetweenwhen the molecular alignment is in a direction substantiallyperpendicular to both the cathode 2 and the anode 6. It is clearlyunderstood that the electric current density shows a sharp increase atlow voltages when molecular alignment is in the parallel direction.

[0145]FIG. 4B is a graph illustrating a relationship between bothvoltages applied between the cathode 2 and the anode 6, and lightintensity of the luminescent layer 4. In the graph, black dots indicatethe relationship therebetween when the molecular alignment is in adirection substantially parallel to both the cathode 2 and the anode 6,and white dots indicate the relationship therebetween when the molecularalignment is in a direction substantially perpendicular to both thecathode 2 and the anode 6. It is, also, clearly understood that lightintensity of the luminescent layer 4 shows a sharp increase at lowvoltages when molecular alignment is in the parallel direction.

[0146] The structure of the surface light-emitting device applicable tothe present invention is not limited to that depicted in FIG. 1. FIGS.5A through 8C are sectional views showing examples of the structures ofsurface light-emitting devices applicable to the present invention. FIG.5A shows the structure of the surface light-emitting device shown inFIG. 1.

[0147] In all the surface light-emitting devices shown in FIGS. 5Athrough 6B, either one of the anode 6 or the cathode 2 thereof is formedin a shape substantially corresponding to the patterns of interferencefringes of holograms.

[0148] In this way, the shape corresponding to the patterns ofinterference fringes of holograms can be formed easily and accuratelybecause both the anode 6 and the cathode 2 are easy-to-form electrodes.

[0149] In the structure of the surface light-emitting devices shown inFIGS. 5A through 5C out of the drawings mentioned above, all the anodes6 are formed as transparent electrodes in a shape substantiallycorresponding to the patterns of interference fringes of holograms andthe light from the luminescent layer 4 is emitted through the anode 6.

[0150] In this way, the light emitted correspondingly to the patterns ofinterference fringes from the luminescent layer 4 comes out externallythrough the anode 6 formed in a shape substantially corresponding to thepatterns of interference fringes as a result of applying a voltagebetween the anode 6 and the cathode 2. Consequently, light reproducedwith high fidelity to the patterns of interference fringes may beobtained.

[0151] In the surface light-emitting devices shown in FIGS. 5A and 5Bout of the drawings mentioned above, all of these devices dispose theglass substrates 8 at a position outside of the cathodes 2 whileemitting the light from the luminescent layer 4 through the anodes 6.

[0152] In this way, the light from the luminescent layer 4 can beemitted externally without passing through the glass substrate 8. As aconsequence, the light comes out without much degradation of the lightamount.

[0153] In the surface light-emitting device depicted in FIG. 5A out ofthe drawings, the anode 6 alone is formed in a shape substantiallycorresponding to the patterns of interference fringes.

[0154] In this manner, the anode 6 can be formed in a shapesubstantially corresponding to the patterns of interference fringeseasily and more precisely because no patterning of the remaining layersis required.

[0155] Both the anode 6 and the luminescent layer 4 are formed in thepatterns of interference fringes in the surface light-emitting devicedepicted in FIG. 5B.

[0156] In the surface light-emitting devices shown in FIGS. 5C, theglass substrate 8 having transparency is disposed at a position outsideof the anode 6, and the light from the luminescent layer 4 is emittedthrough the anode 6 and the glass substrate 8.

[0157] Consequently, the anode 6 formed in the patterns of interferencefringes can be provided on the glass substrate 8 after disposing thesubstrate 8 prior to providing the anode 6 thereon. As a result, theanode 6 can be formed easily and more precisely to the patterns of theinterference fringes.

[0158] In both the surface light-emitting devices shown in FIGS. 6A and6B, the cathodes 2 are formed substantially in the patterns ofinterference fringes and the anodes 6 are formed as transparentelectrodes while emitting the light from the luminescent layers 4through the anodes 6.

[0159] Under the structure described above, the cathode 2 formed in ashape corresponding to the patterns of interference fringes not to betransparent electrodes. In this way, the cathode 2 can be formed with aneasy-to-form material. Consequently, the cathode 2 can easily andaccurately be formed in the patterns of interference fringes.

[0160] In both the surface light-emitting devices shown in FIGS. 6A and6B, the glass substrate 8 having transparency is disposed at a positionoutside of the anode 6 and the light from the luminescent layer 4 isemitted through the anode 6 and the glass substrate 8.

[0161] Consequently, these surface light-emitting devices can easily befabricated by using an element including transparent electrodes formedon the glass substrate 8 readily available.

[0162] In the surface light-emitting device shown in FIG. 6A out of thedrawings mentioned above, just the cathode 2 alone is formed in a shapesubstantially corresponding to the patterns of interference fringes ofholograms.

[0163] Consequently, the cathode 2 can further be formed in the patternsof interference fringes easily and accurately because the layers otherthan the cathode 2 are not necessary to be patterned.

[0164] In the surface light-emitting device shown in FIG. 6B, both thecathode 2 and the luminescent layer 4 are formed in a shapesubstantially corresponding to the patterns of interference fringes.

[0165] Further, in a surface light-emitting device shown in FIG. 7, ashielding layer 20 formed in a shape substantially corresponding to thepatterns of interference fringes of holograms, is disposed at a positionoutside of the luminescent layer 4 and the light from the luminescentlayer 4 is emitted through the shielding layer 20.

[0166] In this way, light corresponding to the patterns of interferencefringes can easily be emitted by using the shielding layer 20 as a maskfor the light emitted from the luminescent layer 4.

[0167] As a consequence, the shielding layer 20 may be formed with aneasy-to-form material because not many restrictions exist on thematerial for the shielding layer 20. Consequently, the shielding layer20 can easily and accurately be formed in the patterns of interferencefringes. Although, there is no specific limitation on the materials ofthe shielding layer 20, for example, Au and the like may be used for thelayer 20.

[0168] Further, the anode 6 is formed as a transparent electrode whiledisposing the shielding layer 20 at a position outside of the anode 6 inthe surface light-emitting device shown in FIG. 7. In this manner, theentire portion of the luminescent layer 4 illuminates by applying avoltage between the anode 6 and the cathode 2, so that a part of theresulting light can be emitted through the shielding layer 20 formedcorresponding to the patterns of interference fringes as a mask.Consequently, light reproduced with high fidelity to the patterns ofinterference fringes may be obtained.

[0169] Still further, the glass substrate 8 having transparency isdisposed at a position outside of the shielding layer 20 and the lightfrom the luminescent layer 4 is emitted through the anode 6, theshielding layer 20, and the glass substrate 8 in the surfacelight-emitting device depicted in FIG. 7.

[0170] In this manner, the shielding layer 8 formed in a shapecorresponding to the patterns of interference fringes can be formed onthe glass substrate 8 prepared before forming the shielding layer.Consequently, a shape corresponding to the patterns of interferencefringes can easily and accurately be obtained.

[0171] In both the surface light-emitting devices shown in FIGS. 8A and8B, an uneven transparent layer formed unevenly in thicknesssubstantially corresponding to the patterns of interference fringes, isdisposed at a location outside of the luminescent layer 4, and the lightfrom the luminescent layer 4 is emitted through the transparent layer.

[0172] In this way, light corresponding to the patterns of interferencefringes can be emitted as a result of illuminating the light from theluminescent layer 4 through the uneven transparent layer. In addition,easy-to-form material(s) can be selected from various materials for theuneven transparent layer because the uneven transparent layer has notmany restrictions on its material. As a consequence, the uneventransparent layer can easily and accurately be formed in a shapecorresponding to the patterns of interference fringes.

[0173] Further, the structures of the surface light-emitting devicesdepicted in FIGS. 8A and 8B are characterized in that, the anode 6 isformed as a transparent electrode and the uneven transparent layer isdisposed at a position outside of the anode 6.

[0174] In this manner, the entire portion of the luminescent layer 4illuminates by applying a voltage between the anode 6 and the cathode 2,so that the resulting light can be emitted through the uneventransparent layer formed unevenly in thickness substantiallycorresponding to the patterns of interference fringes. Consequently,light reproduced with high fidelity to the patterns of interferencefringes may be obtained.

[0175] In the surface light-emitting device shown in FIG. 8A out of thedrawings, the uneven transparent layer is formed as a glass substrate 22having transparency and the light from the luminescent layer 4 isemitted through the anode 6 and the glass substrate 22.

[0176] As a consequence, a shape corresponding to the patterns ofinterference fringes can easily and accurately be obtained by justforming convex/concave patterns corresponding to the patterns ofinterference fringes on the surface of the glass substrate 22 havingtransparency.

[0177] In the surface light-emitting device shown in FIG. 8B, on theother hand, the uneven transparent layer is formed as a passivationlayer 24 having transparency and the light from the luminescent layer 4is emitted through the anode 6 and the layer 24.

[0178] Consequently, a shape corresponding to the patterns ofinterference fringes can be obtained easily and accurately by justforming concave and convex corresponding to the patterns of interferencefringes on the surface of the layer 24.

[0179] Subsequently, embodiments of the present invention to realize alight source suitable for the reproduction of holograms will bedescribed.

[0180] One of such embodiments will be described with reference to FIGS.9 through FIG. 10B. As shown in FIG. 9, an active thickness (opticaldepth) v of the luminescent part 26 emitting light in the luminescentlayer 4 can be formed in a thickness negligible (approximately 5nano-meters) in comparison with the wavelength of the emitted light (asdescribed above) when the luminescent layer 4 is made of organicmaterial(s).

[0181] However, an imaginary light source 28 created by reflection ofthe light directed to the backside (a direction other than apredetermined optical path) is located at a position apart from theluminescent part 26. The light source can not keep its optical depthnarrow if the imaginary light source 28 is located at such a position.In other words, the depth of the imaginary light source 28 substantiallybecomes approximately to 2u1 unexpectedly when an optical distancebetween the luminescent part 26 and a reflective plane 30 forming thesurface of the cathode 2 is defined as u1.

[0182] There might be too many restrictions on the reproduction ofholograms if the optical distance is in an unexpected depth. Therestriction might cause the following problems such as; 1) the spatialcoherence is unexpectedly lowered, 2) the holograms need to be handledas thick holograms and so on.

[0183] In order to avoid such restrictions, the anode 6 is formed as atransparent electrode and the reflective plane 30 is disposed on thesurface of the cathode 2 so that both the light go through the anode 6and the light reflected on the reflective plane 30 are incorporated soas to intensify the resulting light as shown in FIG. 10A.

[0184] For example, an optical distance u1 between the luminescent part26 and the reflective plane 30 of the cathode 2 may be defined as thefollowing equation;

u1≈(2n−1)λ/4

[0185] wherein “n” is a positive integer, and “λ” equals to a wavelengthof the light desirably emitted from the device.

[0186] As shown in FIG. 10B, phase of reflected light of the lightdirected to the backside (to the cathode 2) of the luminescent layer 4therefrom (see FIG. 10B (b)) and that directed to the front-side (to theanode 6) therefrom (see FIG. 10B (a)) are nearly matched. It is,therefore, possible to emit light suitable for the reproduction ofholograms.

[0187] Amplitude of the resulting light Hc (see FIG. 10B (c)) may becalculated under the equation below when amplitude of the lightsdirected to the front-side and reflected light of the light directed tothe back-side of the luminescent layer 4 therefrom respectively definedas “Ha” and “Hb”;

Hc≈Ha+Hb.

[0188] In other words, the resulting light having a higher intensitythan that of the light emitted from the luminescent layer 4 can beobtained by forming the device as shown in FIG. 10A. Consequently, it ispossible to provide a surface light-emitting device realizing the lightsource much suitable for the reproduction of holograms.

[0189] Subsequently, another embodiment realizing a light source muchsuitable for the reproduction of holograms will be described withreference to FIGS. 1A through 12B.

[0190] As shown in FIG. 11A, in this embodiment, an anode 6 in thedevice is formed as transparent electrodes, and a cathode 2 is formed asan electrode reflecting lights access thereto. Both a light-emittinglayer 4 and a hole transport layer 14 are disposed between the cathode 2and the anode 6 in that order. In addition, four pairs of dielectricmirrors 36 forming a dielectric reflective layer are disposed at aposition outside (at the side light emits therefrom) of the anode 6 soas to build up a stacked layer. Each of the mirrors 36 is formed of astacked-structure composed of an oxide titanium layer 32 and a siliconoxidation layer 34 formed in that order.

[0191] By forming the device as described above, the light from theluminescent layer 4 is resonated between the reflective plane 30 of thecathode 2 and reflective planes of the mirrors 36 (inner planes of themirrors 36), and the light thus resonated is emitted.

[0192] For example, another optical distance u2 between the reflectiveplane 30 of the cathode 2 and one of the reflective planes of the mirror36 may be defined as the following equation;

U2≈nλ/2

[0193] wherein “λ” represents a wavelength of the light desirablyemitted from the device.

[0194] The device fabricated under the structure described above canobtain monochromatic radiation having a high intensity effectively witha simple structure. Also, light having a high directivity can beobtained with the device as well. Lights having similar phase canfurther be obtained. In other words, it is possible to provide a surfacelight-emitting device realizing the light source suitable forreproduction of holograms.

[0195]FIGS. 11A through 12B are views illustrating a case in which thewavelength λ of the light desirably emitted from the device is 490nano-meters. In these examples, the oxide titanium layer 32 and thesilicon oxidation layer 34 both composing a pair of the mirror 36 arerespectively formed 61 nano-meters and 96 nano-meters in thickness. Theoptical distance of the two pairs of the mirrors 36 provided adjacent tothe anode 6 is approximately 1.1λ because index of refraction of theboth the oxide titanium layer 32 and the silicon oxidation layer 34 isrespectively 2.3 and 1.45.

[0196] The luminescent layer 4, the hole transport layer 14, and theanode 6 are respectively formed as 30 nano-meters, 40 nano-meters, and40 nanometers in thickness. A sum total of the optical distance acrossthe luminescent layer 4, the hole transport layer 14, and the anode 6becomes approximately 0.4λ because index of refraction of both theluminescent layer 4 and that of the hole transport layer 14 is 1.7, andthat of the anode 6 (ITO layer) is 1.9.

[0197] As a result, an optical distance between the reflective plane 30of the cathode 2 and the reflective plane in the third pair of themirror 36 becomes approximately 3/2λ. In other words, it is apparentthat the emitted light is in a resonant condition. Light having similarphase further can be obtained by making the emitted light in theresonant condition.

[0198]FIG. 11B is a graph illustrating spectra of the emitted light fromthe device shown in FIG. 11A using radiation degrees of the light asparameters. It is apparent from the graph that these lights have anarrower frequency range (much like monochromatic radiation) with higherlight intensity in comparison with the lights without providing themirrors 36.

[0199]FIG. 12A is a graph illustrating radiation patterns of the emittedlights from the device shown in FIG. 11A. Also, FIG. 12B is a graphillustrating radiation patterns of emitted lights from the devicewithout the mirrors 36 It is apparent from both the graphs shown inFIGS. 12A and 12B that directivity of the emitted lights becomes keen byproviding the mirrors 36 thereto.

[0200] Subsequently, another embodiment of the present invention torealize a light source suitable for the reproduction of holograms willbe described with reference to FIGS. 13A and 13B.

[0201] As shown in FIG. 13A, both an anode 6 and a cathode 2 in a deviceof this embodiment are formed as transparent electrodes. In addition, aluminescent layer 4 is disposed between the anode 6 and the cathode 2.

[0202] Most of lights (shown in a dotted line) directed to the backside(other direction than a predetermined optical path) out of the lightsemitted from a luminescent part 26 are not reflected and go straight tothe backside by forming both the anode 6 and the cathode 2 astransparent electrodes as a result of suppressing its reflection factorsin a lower level. In this way, the light source never widens itspractical optical depth.

[0203] As a consequence, localization of an imaginary light sourcecreated by reflection of the lights directed to the backside to aposition other than that of the luminescent part 26 may be avoided bypermitting the travel of most of the lights go to the backside from theluminescent layer 4 in the backward-direction.

[0204] As a result, the light source can keep its optical depth narrow.There is no probability to interfere phase of the lights directed to thefront-side (shown in actual line) with reflection of the lights directedto the backside (shown in dotted line). It is, therefor, possible toobtain the lights suitable for reproduction of holograms.

[0205] Although, glass substrates are used as the supporting member inthe embodiments described earlier, there is no limitation to use theglass substrates as the supporting member. Any other substratesappropriate such as substrates made of synthetic resin may also be usedas the supporting member. In addition, substrates having no transparencymay also be used for the supporting member.

[0206] Although, the electrodes in the embodiments described earlier areformed as pairs of electrode layers (anode 6 and cathode 2) so as tointerpose the light-emitting players 4, any other structures may also beemployed.

[0207] Alternatively, organic materials forming the luminescent layersare disposed in a direction substantially parallel to the electrodes inthe embodiments described earlier, the molecular alignment of theorganic materials is not limited to that direction. For example, organicmaterials forming the luminescent layers may also be disposed in adirection substantially perpendicular to the electrodes.

[0208] Although, organic materials are used for the luminescent layersin the earlier embodiments, the materials of the luminescent layers arenot limited to organic materials. For example, inorganic material(s) mayalso be used for the luminescent layers.

[0209] The anode 6, the cathode 2, the shielding layer 20 and so on areexampled as hologram layers corresponding to the patterns ofinterference fringes of holograms in the earlier embodiments. Thehologram layers are not limited to these layers. For example, theluminescent layer 4, the hole transport layer 14, the electron transportlayer 16, and the hole injection layer 18 and so on may also be used asthe hologram layers. In addition, the hologram layer may be formed bycombining any of these layers. In short, a hologram layer formedsubstantially corresponding to the patterns of interference fringes ofholograms should be disposed either on a layer related to light emissionor on an optical path for emitting lights from the luminescent layer.

[0210] Although, patterns of holograms of a condensing lens forming anoptical element are exmapled in the earlier embodiments, the hologrampatterns of the optical element are not limited to these patterns.Hologram patterns of other lenses such as that of a collimator lens, aconcave lens and so on may also be used as the patterns of holograms. Inaddition to hologram patterns of those lenses, hologram patterns of anyother optical elements for example, hologram patterns of mirrors such asa flat-surface mirror, a curved-surface mirror and so on, hologrampatterns of transparent glasses, that of diffusing board such as frostedglasses may also be used depending on the usage. Hologram patternscombining any of these elements can also be used as the patterns ofholograms.

[0211] In the earlier embodiments, hologram patterns of the opticalelements are used as the patterns of interference fringes of holograms,the usage of the patterns of interference fringes of holograms is notlimited to the hologram patterns of the optical elements. It is,therefore, possible to use the patterns of interference fringes ofholograms, for example, created by a combination of optical element(s)and another object(s), and that created by object(s) other than theoptical element(s) as the patterns of interference fringes of holograms.

[0212] Although, the beam generators are used for the optical pickupdevices in the above-described embodiments, the usage of those beamgenerators is not limited to that. As applicable items of the beamgenerator, for example, barcode-readers, laser printers, flash lights,turn signals for an automobile and other vehicles, laser pointers usinglaser beams may be exampled.

[0213] Further, the usage of the surface light-emitting devicesaccording to the present invention is not limited to the device used forthe beam generator, it can also applicable generally to a surfacelight-emitting device for an optical-input/output device, for example,one for an image display device.

[0214] Chapter 2

[0215]FIG. 14 is a sectional view for describing the structure ofanother beam generator 40 according to another embodiment of the presentinvention. The beam generator 40 comprises stacked-layers formed of acathode 2 acting as an electrode layer, a luminescent layer 4 and ananode 6 forming another electrode layer in that order, thestacked-layers being located adjacent to a glass substrate 8 forming asupporting body.

[0216] The cathode 2 is formed in a shape substantially corresponding tothe patterns of interference fringes of holograms. The cathode 2 forms ahologram layer. In other words, arrangement of portions 2 a, 2 b, 2 c, 2d, and so on composing the cathode 2 correspond to the patterns ofinterference fringes of holograms.

[0217] Each of the portions 2 a, 2 b, 2 c, 2 d, and so on composing thecathode 2, and the anode 6 are connected to a control part 42. A DCvoltage is applied to both the portions 2 a, 2 b, 2 c, 2 d, and so on,and the anode 6 in accordance with the control of the control part 42.All the components of the beam generator 40 except for the control part42 form a surface light-emitting device.

[0218] In this embodiment, description of the present invention will bemade under an assumption in which the beam generator 40 is applied to anoptical pickup device. It is also assumed that patterns of holograms ofa condensing lens forming an optical element, are used as the patternsof interference fringes of holograms.

[0219]FIG. 15 is a plan view illustrating typical planar structure ofhologram layers (the cathode 2, in this embodiment). FIG. 16 is a viewillustrating typical patterns of interference fringes themselvescorresponding to the hologram layers shown in FIG. 15.

[0220] The hologram layer shown in FIG. 15 includes both light-pattern44 and dark-pattern 46. In this embodiment, the light-pattern 44correspond to the portions 2 a, 2 b, 2 c, 2 d, and so on, shown in FIG.14. The dark-pattern 46 correspond to the parts situated between theportions 2 a, 2 b, 2 c, 2 d, and so on. Portions corresponding to thelight-pattern 44 shown in FIG. 15 out of the luminescent layer 4 emitlight when a DC voltage is applied between the cathode 2 and the anode 6shown in FIG. 14, so that portions corresponding to the dark-pattern 46not illuminates light.

[0221] It is known that holograms can be reproduced even with a part ofthe interference fringes of the holograms. In this embodiment, ahologram layer is formed by using patterns located periphery (see FIG.16) of the interference fringes of the holograms alone.

[0222] The reason of using the peripheral patterns is described withreference to FIG. 17. FIG. 17 is a view illustrating a typical conditionin which collimated light is directed to ordinary transmission-typeholograms HG on which a hologram pattern of the condensing lens isformed in a direction of arrows extending from the left-hand side to theright-hand side of the drawing.

[0223] It is known that directivity of lights after passing throughholograms HG (on the side of a light path toward the holograms HG)depending upon the conditions of the lights before passing therethrough(on the opposite side of the light path toward the holograms HG) and adistance between the interference fringes of the holograms HG.

[0224] According to the principle, directivity of lights after passingthrough holograms HG receives much influence of the conditions of thelights before passing therethrough than that created by a distance d ofthe fringe because the distance d is wider (d=d2) at vicinity of thecenter of fringes (bottom of FIG. 17). In this way, the directivity mustdirectly reflect the conditions of the lights before passing theholograms HG at positions adjacent to the center of the fringes.

[0225] The directivity of lights after passing through holograms HG, onthe other hand, receives much influence of the distance d of the fringesthan that created by the conditions of the lights before passingtherethrough because the distance d is narrower (d=d1) at vicinity ofthe periphery of fringes (top of FIG. 17).

[0226] As a consequence, directivity of lights possibly be controlled inaccordance with the distance d departing from the conditions of thelights before passing through the hologram HG at positions adjacent tothe center of the fringes.

[0227] In other words, it is possible to realize a hologram layersuitable for the reproduction of holograms by using the patterns locatedperiphery of the interference fringes of the holograms alone.

[0228] In this embodiment, a width Δx of the light-pattern 44 issubstantially formed in a range of a wavelength of the light or lessthan said range as shown in FIG. 15. As a consequence, the width Δx ofthe light-pattern 44 could be narrower than that of the interferencefringes originally recorded on the hologram layers shown in FIG. 16 insome places. The distance (pitch) d between the light-patterns 44 isequal to a distance d between the originally recorded interferencefringes shown in FIG. 16.

[0229] The reason of narrowing the width Ax of the light-pattern 44 willbe described with reference to FIG. 17. It is known that the directivityof lights after passing through the holograms HG, also, depending uponconditions of the lights before passing therethrough as well as thewidth of transparent portions TP out of the interference fringes of theholograms HG.

[0230] According to the theory, the directivity of lights after passingthrough holograms HG receives much influence of the conditions of thelights before passing therethrough at a transparent portion TP having awider width (x=x2), particularly at a portion adjacent to the center ofthe interference fringes of the holograms HG. In this way, the lightdirectivity must be largely influenced by the conditions of the lightsbefore passing through the hologram HG at the portion having a widerwidth x.

[0231] The light directivity, on the contrary, receives not muchinfluence of the conditions of the lights before passing therethrough ata transparent portion TP having a narrower width (x=x1), particularly ata portion located periphery of the interference fringes of the hologramsHG.

[0232] It is considered that the light directivity can be controlledregardless of the conditions of the lights before passing through thehologram layer if the hologram layer is formed so as to narrow the widthΔx of the light-pattern 44 as shown in FIG. 15. In other words, ahologram layer much suitable for reproduction of holograms may berealized.

[0233] In addition, light intensity of the holograms is reproduced byadjusting brightness of the portions in the luminescent layer 4corresponding to the light-pattern 44 while narrowing each light-pattern44 in a fixed width Δx as shown in FIG. 15 in this embodiment.

[0234] The brightness of the portions in the luminescent layer 4 wherecorrespond to each light-pattern 44 is controlled by adjusting a currentvalue flowing through the portions out of the luminescent layer 4.

[0235] In a concrete form, the brightness of the portions wherecorresponding to each light-pattern 44 is controlled by respectivelyadjusting current values flowing through the luminescent layer 4 viaeach of the portions 2 a, 2 b, 2 c, 2 d, and so on composing the cathode2 in accordance with the control of the control part 42 shown in FIG.14. Information containing phase of the holograms may be reproduced byallocating each light-pattern 44 (pattern element).

[0236] In this way, the hologram layer can be formed by just allocatingeach of the light-patterns 44 having the fixed width A x at properlocations. Consequently, the hologram layer can be formed easily.Further, the information containing light intensity of the holograms mayeasily be reproduced by just controlling current values flow through theportions out of the luminescent layer 4 corresponding to each of thelight-patterns 44. In other words, it is possible to realize a hologramlayer suitable for the reproduction of holograms.

[0237] In order to fabricate a surface light-emitting device used forthe beam generator 40 depicted in FIG. 14, the following steps need tobe carried out. A layer made of metals and the like for forming thecathode 2 is formed on the surface of the glass substrate 8 byevaporation method or the like. Then, the metal layer is patterned in ashape corresponding to the interference fringes by etching process orthe like. On the patterned metal layer, another layer made of organicmaterials for forming the luminescent layer 4 is formed by vacuumevaporation process or the like, and another layer made of oxidematerials for transparent electrodes for forming the anode 6 is formedon the organic layer by evaporation method.

[0238] The operation of the beam generator 40 will be described.Electric currents, each having a predetermined value flow respectivelythrough the portions 2 a, 2 b, 2 c, 2 d, and SQ on composing the cathode2. In this way, portions out of the luminescent layer 4 between theportions 2 a, 2 b, 2 c, 2 d, and so on composing the cathode 2 and theanode 6 illuminate light.

[0239] As described earlier, allocation of the portions 2 a, 2 b, 2 c, 2d, and so on corresponds to that of the interference fringes ofholograms on the condensing lens (see FIG. 16), and the current valuesflowing through the portions 2 a, 2 b, 2 c, 2 d, and so on respectivelycorrespond to the information containing light intensity of theholograms of the condensing lens. As a consequence, the light from theluminescent layer 4 is focused on the focal point of the condensing lensas a result of proceeding the light in a direction of optical path (adirection in which a compact disc CD and the like is allocated) throughthe anode 6.

[0240] The compact disc CD is allocated at a position so that the focalpoint of the condensing lens is on the recording layer (not shown)thereof. The data recorded on the recording layer are read out bydetecting the amount of light reflected thereby.

[0241] As described above, the cathode 2 is formed in a shapesubstantially corresponding to the hologram patterns of the condensinglens. In this way, a part of the luminescent layer 4 illuminates lightcorrespondingly to the hologram patterns of the condensing lens byflowing appropriate electric currents through the cathode 2 and theanode 6.

[0242] As a consequence, the surface light-emitting device alone can beused for both the light source and the condensing lens. Consequently,the beam generator 40 can be manufactured with compact-profile and inreasonable cost by using the surface light-emitting device according tothe present invention.

[0243] Although, the width of the light-pattern composing the hologramlayer is substantially formed in a range of a wavelength of the light orless than said range in the above embodiment, the width can be formed ina range substantially exceeding the wavelength.

[0244] Although, light intensity of the holograms is reproduced byadjusting brightness of the portions corresponding to the light-patternwhile making each light-pattern in a fixed width in the aboveembodiment, the brightness of the portions may be fixed to a certaindegree while making the width of the each light-pattern in a widthcorresponding to that of the interference fringes of the hologramsoriginally recorded.

[0245] In the above embodiment, the hologram layer is formed alone witha part located periphery of interference fringes of the hologram, anyother portions may also be used for forming the hologram layer forms thehologram layer.

[0246] All the descriptions in the chapter 1 are applied to this chapterunless otherwise they are not clearly applicable to this chapter. Forexample, the description on materials of the luminescent layer 4, theanode 6 and that of the cathode 2, each composing the surfacelight-emitting device, and the description on stacked layer structure ofthe device referring to FIGS. 2 through 13 may also be applicable tothis chapter.

[0247] Chapter 3

[0248]FIG. 18 is a sectional view for describing the structure of anoptical pickup device 50 forming not only a light-input/output devicebut also a device for monitoring reflected light using a surfacelight-emitting device according the present invention. The opticalpickup device 50 comprises a stacked-layer formed of anon-light-transparent layer 52, a cathode 2 acting as an electrodelayer, a luminescent layer 4 and an anode 6 forming another electrodelayer in that order, the stacked-layer being located adjacent to a glasssubstrate 8 forming a supporting body.

[0249] The non-light-transparent layer 52 includes a plurality ofportions 52 a, 52 b and so on. The cathode 2 also comprises a pluralityof portions 2 a, 2 b and so on. The luminescent layer 4 includes aplurality of portions 4 a, 4 b and so on. The anode 6 is composed of aplurality of portions 6 a, 6 b and so on.

[0250] The stacked-layer including the non-light-transparent layer 52,the cathode 2, the luminescent layer 4 and the anode 6 is substantiallyformed in patterns corresponding to the patterns of the interferencefringes of the holograms. Three layers such as the cathode layer 2, theluminescent layer 4 and the anode layer 6 out of layers in thestacked-layer form the hologram layer. The hologram patterns of thecondensing lens forming the optical element are used as the patterns ofthe interference fringes of the holograms. Each of the portions 2 a, 2 band so on forming the cathode 2 and the portions 6 a, 6 b and so oncomposing the anode 6 are respectively connected a control part 54. Adirect current flow through each of the portions 2 a, 2 b and so on andthe portions 6 a, 6 b and so on under the control of the control part54. As described earlier, the portions 52 a, 52 b and so on composingthe non-light-transparent layer 52 are disposed between the portions 2a, 2 b and so on forming the cathode 2 and the glass substrate 8.

[0251] A detector 56 forming an optical sensor is allocated at aposition behind the glass substrate 8 (on the left-hand side in thedrawing). The detector 56 is controlled by the control part 54. The dataread out with the detector 56 is outputted externally through thecontrol part 54. All the components of the optical pickup device 50except for both the control part 54 and the detector 56 form the surfacelight-emitting device.

[0252] For simplicity, it is assumed that FIG. 15 is a plan viewillustrating typical planar structure of hologram layers (astacked-layer composed of the cathode 2, the luminescent layer 4, andthe anode 6, in this embodiment), and another assumption is made thatFIG. 16 is a typical view illustrating the patterns of interferencefringes of the holograms themselves corresponding to the hologram layerdepicted in FIG. 15.

[0253] The hologram layer depicted in FIG. 15 is composed of thelight-pattern 44 and the dark-pattern 46. In this embodiment, forexample, a stacked body composed of the portion 2 a forming the cathode2, the portion 4 a of the luminescent layer 4, and the portion 6 aforming the anode 6, and another stacked body composed of the portion 2b of the cathode 2, the portion 4 b forming the luminescent layer 4, andthe portion 6 a of the anode 6, and so on depicted in FIG. 18 form thelight-pattern 44. On the other hand, the portions between the stackedbodies form the dark-pattern 46. As a consequence, both thelight-pattern 44 and the dark-pattern 46 make patterns corresponding tothe hologram patterns of the condensing lens.

[0254] The portion corresponding to the light-pattern 44 illuminateslight and that corresponding to the dark-pattern 46 not illuminateslight when a direct voltage is applied between the cathode 2 and theanode 6 shown in FIG. 18, both the portions being depicted in FIG. 15.

[0255] In addition, the light from the luminescent layer 4 travels in aforward-direction (on the right-hand side in the drawing) to the opticalpath but not proceeds in a backward-direction thereto because thenon-light-transparent layer 52 is disposed at the portions correspondingto the light-pattern 44. On the contrary, the light penetrates theportions corresponding to the dark pattern 46 and travels in thebackward-direction because none of the non-light-transparent layer 52 isformed thereon.

[0256] In order to fabricate a surface light-emitting device composingthe pickup device 50 depicted in FIG. 18, the following steps need to becarried out. A layer made of metal and the like which is used for thenon-light-transparent layer 52 is formed on the surface of the glasssubstrate 8, and then another layer made of metal and the like which isused the cathode 2 is disposed thereon by evaporation method or thelike. These metal layers thus formed are patterned in a shapecorresponding to the interference fringes by carrying out etchingprocess or the like. On the patterned metal layers, another layer madeof organic material(s) for forming the luminescent layer 4 and anotherlayer made of oxide material(s) for transparent electrodes for formingthe anode 6 are formed by vacuum evaporation method or evaporationmethod and similar method by utilizing a shadow mask(s) or the like.

[0257] Subsequently, the operation of the pickup device 50 will bedescribed with reference to FIG. 18. Electric currents each having apredetermined value respectively flow between the portions 2 a, 2 b andso on composing the cathode 2 and the portions 6 a, 6 b and so onforming the anode 6. In this way, each of the portions 4 a, 4 b and soon composing the luminescent layer 4 illuminate the light.

[0258] As described earlier, allocation of the portions 4 a, 4 b and soon composing the luminescent layer 4 corresponds to that of theinterference fringes of holograms on the condensing lens (see FIG. 16),and the current values flowing through the portions 4 a, 4 b and so onrespectively correspond to the information containing light intensity ofthe holograms of the condensing lens. As a consequence, the light fromthe luminescent layer 4 (indicated as solid lines in FIG. 18) is focusedon the focal point of the condensing lens as a result of traveling thelight in a direction of optical path (a direction in which a compactdisc CD and the like is allocated) through the anode 6. The light fromthe luminescent layer 4 never travels in a backward-direction (to theleft-hand side in the drawing) to the optical path because of theexistence of the non-light-transparent layer 52 as described earlier.

[0259] The compact disc CD is allocated at a position so that the focalpoint of the condensing lens is focused on the recording layer (notshown) thereof. The reflected light from the recording layer (indicatedas dotted lines in FIG. 18) travels in the backward-direction to theoptical path and returns to the hologram layer. A part of the reflectedlight pass through the dark-pattern 46 and further travels in thebackward-direction to the optical path.

[0260] As described earlier, not only the light-patter 46, but also thedark-pattern 46 are patterns corresponding to the hologram patterns ofthe condensing lens. The reflected light passing through thedark-pattern 46 is focused on another focal pint of the condensing lenslocated in the backward-direction to the optical path of the hologramlayer. The detector 56 is disposed at a position so that the opticalsensing portion thereof (not shown) is situated on the focal point. Thedata recorded on the recording layer of the CD and other data recordingmediums are read out by detecting the amount of light reflected therebywith the detector 56.

[0261] The stacked layer composed of the cathode 2, the luminescentlater 4, and anode 6, is used as the hologram layer while the light onceemitted is returns through the hologram layer in this embodiment.

[0262] In this way, the light source, lens and the half mirror can bereplaced with just the surface light-emitting device by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, theoptical pickup device 50 can be manufactured with compact-profile and inreasonable cost by using the surface light-emitting device according tothe present invention. Followings are features of the surfacelight-emitting device used in this embodiment: the hologram layer iscomposed of the light-pattern 44 and the dark-pattern 46; the lighttravels in a forward-direction to the optical path but not travels in abackward-direction thereto at the portions corresponding to thelight-pattern 44; and the light travels in the backward-direction to theoptical path at the portions corresponding to the dark-pattern 46.

[0263] The light emitted from the light-pattern 44 only travels in theforward-direction and reflected by the recording layer of the CD. Thereflected light passes through the dark-pattern 46 and travels to thebackward-direction of the optical path. As a consequence, the pickupdevice 50 with compact-profile and in reasonable cost can easily berealized by composing the hologram layer with both the light-pattern 44and the dark-pattern 46 described above.

[0264] Further, the non-light-transparent layer 52 formed in a shapecorresponding to the light-pattern 44, is disposed at a position in thebackward-direction of the optical path of the cathode 2.

[0265] In this way, leakage of the light from the light-pattern 44 inthe backward-direction may certainly be avoided. Under thecircumstances, any electrode material(s) for the cathode 2 havingsuperior capabilities of electric charge-injection and formability maybe selected without concerning the capability of light shielding of thecathode 2.

[0266] The structure of the surface light-emitting device capable ofapplying to the present invention is not limited to that shown in FIG.18.

[0267]FIGS. 19A through 19C are sectional views showing examples of thestructures of other surface light-emitting devices applicable to thepresent invention. The structure of a surface light-emitting devicedepicted in FIG. 19 A is the surface light-emitting device removing thenon-light-transparent layer 52 from the device shown in FIG. 18.

[0268] The cathode 2 of the surface light-emitting device is made ofmaterial(s), which is hard to pass through light. In this way, thestructure of the surface light-emitting device may be simplified.

[0269] The structure of a surface light-emitting device depicted in FIG.19B is similar to that of the device shown in FIG. 19A in view offorming the cathode 2 with material(s) which is hard to pass throughlight, but the surface light-emitting device shown in FIG. 19B includesboth a luminescent layer 4 and an anode 6 each formed as a completelayer. In this way, layers can further be formed easily and accuratelyin a shape corresponding to the patterns of interference fringes ofholograms because no patterning of the layers except for the cathode 2is required. In this case, the cathode 2 corresponds to the hologramlayer. Further, the luminescent layer 4 has a certain transparency.

[0270] In a surface light-emitting device depicted in FIG. 19C, aluminescent layer 4 is used as the hologram layer. In other words, theluminescent layer 4 is formed in a shape corresponding to the patternsof interference fringes of holograms. Both the cathode 2 and the anode 6are electrodes having transparency.

[0271] A non-light-transparent layer 52 is disposed at a position in thebackward-direction to the optical path via the cathode 2. Thearrangement of the non-light-transparent layer 52 is exactly the same asthat of the luminescent layer 4.

[0272] All the description in the earlier chapters may be applied tothis chapter unless otherwise they are not clearly applicable to thischapter. For example, the description on materials of the luminescentlayer 4, the anode 6 and that of the cathode 2, each composing thesurface light-emitting device, and the description on layered structureof the device with FIGS. 2 through 4, FIGS. 9 through 12, and FIGS. 15through 17 may also be applicable to this chapter.

[0273] Chapter 4

[0274]FIG. 20 is a sectional view for describing the structure of faranother beam generator 60 forming a light-input/output device using asurface light-emitting device according to another embodiment of thepresent invention. The beam generator 60 comprises a stacked-layerformed of a cathode 2 acting as an electrode layer, a luminescent layer4 and an anode 6 forming another electrode layer in that order, thestacked-layer being located adjacent to a glass substrate 8 forming asupporting body. The cathode 2 forming the hologram layer is composed ofportions 2 a, 2 b, 2 c, 2 d and so on. Each of the portions 2 a, 2 b, 2c, 2 d and so on respectively forms element region (element electrode).

[0275]FIG. 22 is an exploded perspective view of the beam generator 60for describing the structure thereof. As apparent from FIG. 22, all theportions 2 a, 2 b, 2 c, 2 d and so on are formed identical in shape andare allocated in matrix manner. The portions 2 a, 2 b, 2 c and so on areformed on the glass substrate 8, and thin-Film-Transistor (TFT) circuits64 a, 64 b and so on are disposed on the glass substrate 8correspondingly to the portions 2 a, 2 b, 2 c, 2 d and so on. The TFTcircuits 64 a, 64 b and so on form a storing part.

[0276] Selection lines SL0, SL1 and so on for selecting rows in thematrix composed of the portions 2 a, 2 b, 2 c, 2 d and so on and datalines for providing information containing brightness of the portions 2a, 2 b, 2 c, 2 d and so on, are further arranged on the glass substrate8.

[0277]FIG. 23 is a circuit diagram showing a part of the circuits in thebeam generator 60. The TFT circuit 64 a includes a total of twotransistors and one capacitor. Electric charges corresponding toinformation containing its brightness provided through the data lineDL0, are stored in the capacitor while flowing an electric currentcorresponding to the information through a portion corresponding to theportion 2 a out of the luminescent layer 4 when the selection line SL0is selected. In this way, the portion corresponding to the portion 2 ailluminates light under the brightness responding to the informationprovided through the data line DL0. The corresponding portion maintainsits brightness for a predetermined time period (at least a period untilselection of all the selection lines of the surface light-emittingdevice is completed) because of the function of the capacitor even whenthe selection of the selection line SL0 is cancelled. The remaining TFTcircuits 64 b and so on have the same structure as well as the samefunction to that of the TFT circuit 64 a.

[0278] As a consequence, portions in the luminescent layer 4corresponding to each of the portions 2 a, 2 b, 2 c, 2 d, and so oncomposing a row belong to the selection line SL0 simultaneouslyilluminate in a predetermined brightness while maintaining theirbrightness. Thereafter, the portions corresponding to the selection lineSL1 out of the luminescent layer 4 simultaneously illuminate in thepredetermined brightness when the selection line SL1 is in selection.

[0279] In this way, the number of portions illuminating light in theluminescent layer 4 is sequentially increased under the basis of theportion corresponding to one complete selection line. The portions inthe luminescent layer 4 corresponding to all the portions 2 a, 2 b, 2 c,2 d and so on of the cathode 2 simultaneously illuminate in thepredetermined brightness (could be brightness at 0, in other words,there are portions show no illumination) when all the selection linesare selected.

[0280] Reproduction of the holograms can be assured by simultaneouslyilluminating each of the portions corresponding to the portions 2 a, 2b, 2 c, 2 d and so on where brightness thereof are previously determinedcorresponding to the interference fringes of a desired hologram.

[0281] A control part 62 depicted in FIG. 20 comprises the TFT circuits64 a, 64 b and so on. The control part 62 is designed so as to provideinformation containing brightness corresponding to one of the selectedpatterns out of more than one patterns of interference fringes to theTFT circuits 64 a, 64 b and so on. A direct voltage is applied betweeneach of the portions 2 a, 2 b, 2 c, 2 d and so on composing the cathode2 and the anode 6 in accordance with the control of the control part 62.All the components of the beam generator 60 except for the control part62 form the surface light-emitting device.

[0282] In this embodiment, a plotting device using the beam generator 60will be described. Under the circumstances, it is assumed that pluralityhologram patterns of the condensing lens forming an optical element, areprepared as the patterns of interference fringes of holograms.

[0283] Each of the patterns of holograms is designed so as to locate thefocal point of the emitted light from the beam generator 60 on anydesired point of grid points GR defined on a photosensitive plate SPincluded in the device depicted in FIG. 20. The focal point of theemitted light can be located any desired point of the grid points GR byselecting an appropriate hologram pattern and then emitting light.

[0284] It is known that using even a part of the interference fringes ofthe holograms may reproduce the holograms. In this embodiment, theholograms are reproduced by using even a part located periphery of theinterference fringes. As a consequence, the holograms can be reproducedmuch accurately as described above (see FIG. 17).

[0285] Further, the maximum width of each of the portions 2 a, 2 b, 2 c,2 d and so on respectively for meters through 100 nano-meters.

[0286] It is considered that the light directivity can be controlledregardless of the conditions of the lights before passing through thehologram layer if the hologram layer is formed so as to narrow themaximum width of the element regions (see FIG. 17). In other words, ahologram layer much suitable for reproduction of holograms may berealized.

[0287] In order to fabricate the beam generator 60 shown in FIG. 20, thefollowing steps need to be carried out. A layer made of metals and thelike for forming the cathode 2 is formed on the surface of the glasssubstrate 8 by evaporation method or the like. Then, the metal layer ispatterned in a shape corresponding to the interference fringes byetching process or the like. On the patterned metal layer, another layermade of organic materials for forming the luminescent layer 4 is formedby vacuum evaporation process or the like, and another layer made ofoxide materials for transparent electrodes for forming the anode 6 isformed on the organic layer by evaporation method.

[0288] Subsequently, the operation of the beam generator 60 will bedescribed hereunder. Detailed operation thereof, to print analphabetical character “F” shown in FIG. 24, is exampled. Forsimplicity, it is assumed that a total of 96 dots from points P (1,1)through P (12,8) in maximum (12 longitudinal dots by 8 lateral dots) arerequired to do so. Each of the pitches defined among the points P (1,1)through P (12,8) corresponds to that defined among the grid points GRshown in FIG. 20.

[0289] In order to print the character “F”, a total of 34 dots (shown asblack dots in the drawing) out of the 96 dots such as from points P(2,2) through P (11, 3) are used.

[0290] As described earlier, the patterns of holograms of the condensinglens thus prepared are designed so as to locate the focal point of theemitted light from the beam generator 60 on any desired dots of gridpoints GR defined on a photosensitive plate SP included in the devicedepicted in FIG. 20. The surface of the photosensitive plate SP isprecharged and the electric charges on a certain part are eliminatedwhen the light is emitted to the part.

[0291] At first, the control part 62 shown in FIG. 20 selects a hologrampattern by which the focal point of the emitted light is located on agrip point GR corresponding to the point P (2,2) (see FIG. 24). Then,electric currents corresponding to the selected hologram patternrespectively flow through each of the portions 2 a, 2 b, 2 c, 2 d, andso on composing the cathode 2 in accordance with the control of thecontrol part 62.

[0292] As a consequence, the parts in the luminescent layer 4 interposedbetween the portions 2 a, 2 b, 2 c, 2 d, and so on and the anode 6illuminates light correspondingly to the selected hologram pattern. Thelight illuminated from the luminescent layer 4 travels in aforward-direction (a direction in which the photosensitive plate SP isallocated) through the anode 6, and then the light is focused on thegrid point GR corresponding to the point P (2,2) (see FIG. 24). In thisway, a grid point GR corresponding to the point P (2,2) can be exposed.

[0293] Subsequently, the control part 62 selects another hologrampattern by which the focal point of the emitted light is located onanother grid point GR corresponding to the point P (2,3) shown in FIG.24. By carrying similar steps to the exposure of the grid point GRcorresponding to the point P (2,2), the grid point GR corresponding tothe point P (2,3) shown in FIG. 24 is exposed. All the grid pointscorresponding to the points P (2,4) through P (11, 3) shown in FIG. 24are exposed by performing the similar steps described earlier.

[0294] As a consequence, electric charges on the grid points GR definedon the photosensitive plate SP composing the character “F” can beeliminated.

[0295] Thereafter, toner is attracted onto a certain area of thephotosensitive plate SP in accordance with the presence of electriccharges thereon, so that the character “F” may be printed on theprinting paper and the like.

[0296] In the embodiment described above, the cathode 2 is formed as ahologram layer capable of corresponding to the hologram pattern of thecondensing lens while emitting light through a predetermined opticalpath as a result of selecting one of hologram patterns provided to thebeam generator, the emitted light corresponding to the selected hologrampattern. In this way, the beam generator 60 alone functions as both thelight source and the condensing lens.

[0297] In the above embodiment, location of the focal point can be movedeasily on a two-dimensional basis by selecting one of the hologrampatterns out of more than one hologram patterns of the condensing lens.By constructing that way, no mechanical components for mechanicalmovements such as polygon mirror(s) and photosensitive drum arerequired. Consequently, the focal point can be moved easily and speedyon a two-dimensional basis.

[0298] Further, in the conventional type laser printer using both thepolygon mirror and the photo-conductive drum, light need to be scannedall over the drum even to the grid points where no exposure is required.Under the circumstances, a longer period of time is spent for theexposure than it actually required therefor if not many grid points tobe exposed are existed on the drum. In the embodiment described above,on the contrary, the exposure can be performed by just selecting ahologram pattern capable of focusing the light on each of the gridpoints to be exposed, so that an exact time period required for theexposure is spent therefor. In this way, a less time period than thatrequired by the conventional one is spent for the exposure, so that theexposure can be performed speedy.

[0299] In other words, a plotting device characterizing a lightweight,lower-profile, lower-cost, and high-speed operation with durability maybe realized by utilizing the beam generator 60.

[0300] Further, in the embodiment described above, the hologram layer iscomposed of portions 2 a, 2 b, 2 c, 2 d, and so on (element regions),and brightness of portions in the luminescent layer 4 corresponding toeach of the element regions is determined correspondingly to thehologram pattern of the condensing lens while illuminating the portionsin the luminescent layer 4 in the predetermined brightness.

[0301] In this way, a plotting device capable of using a variety ofhologram patterns of a condensing lens can be manufactured by just usingone single beam generator 60 by carrying out the following steps: 1)forming the element regions in a simple shape used various purposes, and2) correspondingly determining brightness of the portions in theluminescent layer 4 corresponding to each of the element regions to thehologram pattern of the condensing lens thus selected. As a consequence,the focal point can be moved flexibly on a two-dimensional basis in theformer example.

[0302] In addition, pluralities of the element regions are substantiallydisposed in a matrix manner in this embodiment. As a result of formingthe beam generator in that way, a plotting device capable of using morevariety of hologram patterns of the condensing lens can be manufacturedby just using one single beam generator 60 by utilizing the elementregions disposed in a matrix manner which can be applied in more widevariety purposes. Consequently, the focal point can further be movedflexibly on a two-dimensional basis in the former example.

[0303] Further, in the embodiment described above, informationcontaining light intensity of the holograms is reproduced in accordancewith brightness of the portions in the luminescent layer 4 wherecorresponding to the element regions. In this case, informationcontaining phase of the holograms may be reproduced in accordance withpositions of the element regions corresponding to the portions under anillumination-state in the luminescent layer 4. In this way, theholograms can be reproduced by varying the brightness of the portionscorresponding to the element regions in the luminescent layer 4.

[0304] In addition, brightness of the portions in the luminescent layer4 corresponding to the element regions is respectively controlled byadjusting current values flowing through the portions in the luminescentlayer 4 corresponding to each of the element regions in this embodiment.In this way, information containing light intensity of the holograms caneasily be reproduced by just adjusting the current values. Consequently,reproduction of the holograms can easily be performed.

[0305] Further, the portions in the luminescent layer 4 corresponding tothe element regions are controlled so as to turn into anillumination-state corresponding to the determined brightnesssubstantially at the same time. In this way, reproduction of theholograms can be performed with certainty.

[0306] Still further, the portions in the luminescent layer 4corresponding to the element regions are capable of maintaining theirillumination-state, and the corresponding portions under a row basis ofthe matrix are controlled so as to sequentially turn into theillumination-state corresponding to the determined brightness and tomaintain the illumination-state in the above-described embodiment.

[0307] In this way, the portions in the luminescent layer 4corresponding to the element regions are simultaneously turned into anillumination-state corresponding to the determined brightness at the endof scanning for all the lines by sequentially scanning the portions inthe luminescent layer 4 corresponding to the element regions under therow basis. Consequently, reproduction of the holograms can easily beperformed with certainty.

[0308] Yet further, the plotting device described earlier is a plottingdevice using the beam generator 60 and is characterized in that, apattern is plotted with beams corresponding to the pattern to be plottedwhich are generated in sequential manner. In this way, a plotting devicecharacterizing lightweight, lower-profile, lower-cost, and high-speedoperation with durability may be realized.

[0309] Further, the TFT circuits 64 a, 64 b, and so on for respectivelystoring current values flowing through the luminescent layercorresponding to each of the element regions are provided in theembodiment described earlier. In this way, illumination-state of eachportion corresponding to each element region can be maintained by juststoring the current values. Consequently, simultaneous illuminationcorresponding to the determined brightness of the portions in theluminescent layer 4 corresponding to the element region can further becarried out easily.

[0310] Although, the beam generator 60 capable of applying to theplotting device using a photosensitive plate SP is described in theearlier embodiment, the present invention is not limited to that. Thebeam generator according to the present invention may also be applied toanother plotting device using a photosensitive drum SD depicted in FIG.43 instead of the photosensitive plate SP.

[0311]FIG. 25 is a sectional view for describing the structure ofanother beam generator 66 according to another embodiment of the presentinvention. The structure of the beam generator 66 is almost the same tothat of the beam generator 60 shown in FIG. 20. Although, the focalpoint of the light is moved on a two-dimensional basis in the beamgenerator 60, the focal point of the emitted light is moved only onone-dimensional basis in the beam generator 66.

[0312] In other words, the hologram patterns designed so as to locatethe focal point of the emitted light on any desired point of grid pointsGR on the photosensitive plate SP are prepared as hologram patterns ofthe condensing lens in the beam generator 60 depicted in FIG. 20.However, hologram patterns designed so as to locate the focal point ofthe emitted light on any desired point of a scanning line SL defined onthe photosensitive drum SD are prepared as hologram patterns of thecondensing lens in the beam generator 66 shown in FIG. 25.

[0313] In this way, light focused with the condensing lens may bedirected to any desired point of the scanning line SL by generating thelight after selecting the hologram pattern in an appropriate manner.

[0314] In this case, the light can be directed to any desired point onthe drum SD by rotating the drum SD in direction shown as R3.

[0315] As a consequence, electric charges on the drum SD correspondingto the points P (2, 2) through P (11, 3) (see FIG. 24) composing thecharacter “F” can be eliminated.

[0316] Thereafter, toner is attracted onto a certain area of thephotosensitive drum SD in accordance with the presence of electriccharges thereon, so that the character “F” may be printed on a printingpaper and the like.

[0317] Although, the maximum width of each element region may be in arange of 10 nano-meters through 100 nano-meters in the embodimentsdescribed earlier, the maximum width of the element regions may also bedefined either of a range less than 10 nano-meters or greater than 100nanometers.

[0318] The surface light-emitting devices composed of a plurality ofelement regions disposed in a matrix manner and including TFT circuitsare exampled in the embodiments described above. The present inventionis not limited to the surface light-emitting device including the TFTcircuits. In addition, the present invention is not limited to thesurface light-emitting devices composed of a plurality of elementregions disposed in a matrix manner.

[0319] Still further, information containing light intensity of theholograms is reproduced in accordance with the brightness of theportions corresponding to the element regions in the devices describedin the above. The information may be reproduced by the number of theelement regions illuminating light under the condition that the portionscorresponding to the element regions are made to certain brightness.

[0320] Yet further, the portions corresponding to the element regionsare controlled so as to sequentially turn into the illumination-statecorresponding to the determined brightness and to maintain theillumination-state in the embodiments described earlier. Thecorresponding portions can be controlled so as to turn into anillumination-state corresponding to the determined brightnesssubstantially at the same time.

[0321] Although, the holograms are reproduced by using only a partlocated periphery of the interference fringes in the embodimentdescribed above, the holograms can also be reproduced by using otherpart of the fringes.

[0322] The structure of the surface light-emitting device applicable tothe present invention is not limited to that depicted in FIG. 20. Forexample, the surface light-emitting devices having the structures shownin FIGS. 5A through 6B, and a surface light-emitting device havinganother structure depicted in FIG. 21 may also be applied to the presentinvention.

[0323] In the surface light-emitting devices shown in FIGS. 5A through6B, the hologram layer is composed either of the anode 6 or the cathode2. In this way, the element regions can be formed easily andappropriately because formation of a certain kind of electrodes such asthe anode 6 or the cathode 2 is relatively easier than others.

[0324] In the surface light-emitting device depicted in FIG. 21, ashielding layer 20 forming the hologram layer is provided at a positionoutside of the luminescent layer 4, and the light from the luminescentlayer 4 is emitted through the shielding layer 20.

[0325] In this way, the light corresponding to the shape of the elementregions can be emitted by passing the emitted light through theshielding layer 20 used as a mask. Material(s) for forming the shieldinglayer 20 may be selected from a wide variety of materials capable ofeasily forming the layer because not much restriction is existed for thematerials of the layer. Consequently, the element regions can be formedeasily and appropriately.

[0326] There is no specific restriction on the material(s) of theshielding layer 20, so that liquid crystal or similar material(s) may beused therefor. In the case of using liquid crystal for the shieldinglayer, the orientation of molecular should be conducted for each ofportions 20 a, 20 b, 20 c and so on of the layer 20 so as to correspondto the hologram pattern.

[0327] The structure of the surface light-emitting device shown in FIG.21 is characterized in that the anode 6 is formed as a transparentelectrode layer while providing the shielding layer 20 at a positionoutside of the anode 6.

[0328] In this manner, the entire portion of the luminescent layer 4illuminates by applying a voltage between the anode 6 and the cathode 2,so that a part of the resulting light can be emitted by using theshielding layer 20 forming the hologram layer as a mask. Consequently,light reproduced with high fidelity to the patterns of interferencefringes may be obtained.

[0329] In the surface light-emitting device depicted in FIG. 21, a glasssubstrate 8 having transparency is disposed at a position outside of theshielding layer 20, and the light from the luminescent layer 4 isemitted through the anode 6, the shielding layer 20 and the glasssubstrate 8.

[0330] In this way, the shielding layer 8 forming the hologram layer canbe formed on the glass substrate 8 after preparing the glass substrate 8having transparency. Consequently, the element regions can be formedeasily and appropriately.

[0331] Although, more than one pattern of interference fringes areprepared and light corresponding to one of patterns selected is emittedthrough the predetermined optical path in the embodiments describedearlier, the present invention may be applicable to a surfacelight-emitting device preparing just one pattern of interferencefringes.

[0332] All the descriptions in the chapters described earlier areapplied to this chapter unless otherwise they are not clearly applicableto this chapter. For example, the descriptions on materials of theluminescent layer 4, the anode 6 and that of the cathode 2, eachcomposing the surface light-emitting devices, and the descriptions onstacked layer structure of the devices referring to FIGS. 2 through 6,FIGS. 9 through 13, and FIG. 17 may also be applicable to this chapter.

[0333] Chapter 5

[0334] Subsequently, FIG. 26 is a view for describing the structure of abarcode reader 70 (light scanning and reading device) according toanother embodiment of the present invention. The barcode reader 70comprises a beam generator 71, a half-mirror 74, a lens 76, and adetector 78.

[0335] The beam generator 71 in the reader, has almost the samestructure to that of the beam generator 60 described earlier (see FIG.20), patterns of holograms of a condensing lens forming an opticalelement are prepared as the patterns of interference fringes ofholograms.

[0336] In the beam generator 71, however, has a hologram pattern bywhich the focal point of the light emitted from the beam generator 71 islocated on any of points of a scanning line SL defined on bar codes BCshown in FIG. 26 unlike to the earlier described beam generator 60having a hologram pattern by which the focal point of the light emittedtherefrom is located on any desired point of grid points GR defined on aphotosensitive plate SP included in the device depicted in FIG. 20.

[0337] In this way, the light thus focused can be sequentially directedto the points on the scanning line SL defined on the bar codes BC alongwith a predetermined scanning direction by selecting appropriatehologram patterns of the condensing lens in accordance with the functionof a control part 72 while emitting the light.

[0338] The structure of the beam generator 71 except for the controlpart 72 is exactly the same to that of the beam generator 60 shown inFIG. 20.

[0339] Subsequently, the operation of the barcode reader 70 will bedescribed hereunder. As described above, all the pluralities of thehologram pattern of the condensing lens are patterns by which the focalpoint of the light emitted from the beam generator 71 is located on anyof points of a scanning line SL defined on bar codes BC shown in FIG.26.

[0340] The control part 72 depicted FIG. 26 controls other components soas to sequentially direct the light focused to the points on thescanning line SL defined on the bar codes BC along with the scanningdirection. In other words, a part of the light emitted from the beamgenerator 71 is focused to the points on the scanning line SL defined onthe bar codes BC sequentially as a result of passing through thehalf-mirror 74.

[0341] A part of the light reflected by the barcodes BC reaches to thedetector 78 as a result of being focused with the lens 76 afterreflecting the reflected light with the half-mirror 74. The datarecorded on the barcodes BC are read out with the detector 78 bydetecting the amount of light detected thereby sequentially.

[0342] For the record purpose, a conceptual view for describing anexample of a prior art barcode reader BR is shown in FIG. 27. The priorart barcode reader BR comprises a laser diode LD, a half-mirror HM, arotary plate RD, and a detector S. A plurality of holograms HG1, HG2 andso on are installed on the same circumference of the plate RD. Further,the reader is designed to rotate the plate RD in a direction RI.

[0343] All the holograms are formed in accordance with the hologrampattern of a condensing lens. The reader is designed to focus the lightspassing through the holograms HG1, HG2 and so on, on the scanning lineSL defined on the bar codes BC shown in FIG. 27 sequentially with apredetermined scanning direction when the lights emitted from the laserdiode LD respectively pass through the holograms in a sequence of theholograms HG1, HG2 and so on.

[0344] In other words, the laser beams emitted from the laser diode LDand then passing through the half-mirror HM are respectively focused onthe points of the scanning line SL defined on the barcode BC through theholograms HG1, HG2 and so on installed on the plate RD in a sequentialmanner.

[0345] A part of the laser beams reflected by the barcodes BC return tothe half-mirror HM via the holograms HG1, HG2 and so on. The lights thusreturned travel to the detector S as a result of the reflection with thehalf-mirror HM. The code printed as the barcode BC is read out with thedetector S by detecting the amount of light detected thereby.

[0346] The prior art barcode reader, however, has the following problemsto solve. The plate RD installing the hologram HG1, HG2 and so on isrotated mechanically in the barcode reader BR. It is, therefore, neitherpossible to operate the reader at high-speed nor to assure itsdurability. To make the matter worse, it is hard to make the readercompact and to manufacture it with a low manufacturing cost.

[0347] The barcode reader 70 shown in FIG. 26 is a barcode reader whichsolve the above-mentioned problems as well as realizing the followingfeatures such as lightweight, compact-profile, reasonable-cost highlydurable, yet capable of operating at a high speed.

[0348] Beams are moved along with the scanning line SL by sequentiallygenerating the beams, the focal point of which is located on any desiredpoint of the scanning line SL without carrying out mechanical movementof the components in the barcode reader 70 depicted in FIG. 26. In thisway, a lightweight, compact-profile, low-cost barcode reader capable ofoperating at a high-speed with durability can be realized.

[0349] Although, the barcode reader in which just one scanning line SLbeing defined has been described in this embodiment, the presentinvention may be applied to a barcode reader including more than onescanning lines SL, the scanning lines SL, for example, three lines SLbeing separately defined at 120 degree with one another. In this case,the barcode reader sequentially scans these scanning lines SL accordingto the function of the control part 72 depicted FIG. 26.

[0350]FIG. 28 is a sectional view for describing the structure ofanother beam generator 80 forming an optical-input/output device usingthe surface light-emitting device according to another embodiment of thepresent invention. The beam generator 80, has almost the same structureto that of the beam generator 60 described earlier (see FIG. 20), andpatterns of holograms of a lens forming an optical element are preparedas the patterns of interference fringes of holograms.

[0351] In the beam generator 80, however, has hologram patterns by whichthe light emitted from the beam generator 80 has different radiationdegree unlike to the earlier described beam generator 60 having ahologram pattern by which the focal point of the light emitted therefromis located on any desired point of the grid points GR defined on aphotosensitive plate SP included in the device depicted in FIG. 20.

[0352] Upon selecting a desired beam with a beam-selecting switch (notshown), a control part 82 performs a series operation as thefollowings; 1) selecting a hologram pattern appropriates for the desiredbeam and then 2) controlling so as to emit light. In this way, beamshaving different radiation degrees can be obtained depending upon itspurpose with the beam generator 80 alone.

[0353] The structure of the beam generator 80 except for the controlpart 82 that is corresponding to a surface light-emitting device isexactly the same to that of the beam generator 60 shown in FIG. 20.

[0354] The usage of the beam generator 80 is not limited to anyparticular purposes, it may be applicable to the followings, forexample, laser pointers, signals for an automobile and other vehicles,flashlights and the like.

[0355] The surface light-emitting devices composed of a plurality ofelement regions disposed in a matrix manner and including TFT circuitsare exampled in the embodiments described earlier. The present inventionis neither limited to the surface light-emitting device including theTFT circuits nor to the surface light-emitting device composed of aplurality of element regions disposed in a matrix manner.

[0356] For example, a surface light-emitting device shown in FIG. 29 canbe used for the surface light-emitting device for the beam generator 80depicted in FIG. 28. The surface light-emitting device shown in FIG. 29comprises a plurality of element regions 84 (corresponding to theportions 2 a, 2 b, 2 c, 2 d and so on shown in FIG. 28) substantiallydisposed in a concentric manner unlike to the element regions beingallocated in matrix manner (the portions 2 a, 2 b, 2 c, 2 d and so ondepicted in FIG. 22) shown in FIG. 22.

[0357] In this embodiment, each of the element regions 84 depicted inFIG. 29 is formed in a range of 10 nano-meters through 100 nano-metersin width. Further, information containing light intensity of theholograms is reproduced in accordance with brightness of the portionscorresponding to the regions 84 by forming the width of the regions 84and its distance in fixed manner in this embodiment.

[0358] For example, a control part 86 controls which one of the elementregions 84 depicted in FIG. 29 should be turn on and which one of heelement regions 84 should be turn off. By changing the element regions84 illuminating light, hologram patterns for plurality kinds of lens canbe realized. In this case, beams having different radiation degrees canbe obtained with the hologram patterns shown in FIGS. 30A and 30B.

[0359] As described above, the beam generator 80 in this embodiment iscomposed of the surface light-emitting device including a plurality ofthe element patterns 84 disposed in a concentric manner. In this way,beams having various modes and different focal points can be realized byusing just one surface light-emitting device as a result ofcorrespondingly determining brightness of the portions corresponding toeach of the element regions 84 disposed in a concentric manner dependingupon the interference fringes of the selected hologram.

[0360] Further, the surface light-emitting device in this embodiment,each of the element regions 84 is formed in a range of 10 nano-metersthrough 100 nano-meters in width. In this way, the element regions 84each having a very narrow in width can be realized. Although, thedirectivity of lights after passing through the hologram is largelyinfluenced by both the conditions of the lights before passing throughthe hologram and the width of the element regions 84 composing thehologram layer, the directivity receives not much influence of theconditions of the lights before passing therethrough if the width of theelement regions 84 is formed in narrower in width.

[0361] It is considered that the light directivity can be controlledregardless of the conditions of the lights before passing through thehologram layer by forming the hologram layer with the element regions 84having a very narrow width. In other words, a hologram layer muchsuitable for reproduction of holograms may be realized.

[0362] Further, the surface light-emitting device in this embodiment,the information containing light intensity of the holograms isreproduced in accordance with brightness of the portions correspondingto the regions 84 while forming the width of the regions 84 in fixedmanner. As a consequence, the regions 84 formed in a fixed width caneasily form a hologram layer capable of using various purposes.

[0363] In this case, information containing phase of the holograms maybe reproduced in accordance with positions of the element regionscorresponding to the portions under an illumination-state in the elementregions 84. In this way, the holograms can be reproduced by varying thebrightness of the element regions 84.

[0364] Although, the surface light-emitting device comprising aplurality of the element regions 84 disposed in a concentric manner isdescribed in the embodiment described above, a surface light-emittingdevice comprising a plurality of the element regions 84 each having apart substantially formed in circular arc shape may be formed. Here, theelement regions 84 each having a part substantially circular arc shapeincludes a concept in which the element region 84 formed in an ovalshaped is included therein. By forming the element regions 84 in thatshape, beams not only having different focal points but also capable ofdirecting the beams in different directions having various modes can berealized.

[0365] Alternatively, each of the element regions 84 is formed in arange of 10 nano-meters through 100 nano-meters in width in theembodiment described above, the width of the light-pattern may be formedin less than 10 nano-meters or more than 100 nano-meters in width.

[0366] In the embodiment described above, though the width of each ofthe element regions 84 is formed in fixed manner, the width of eachregion 84 may be formed differently.

[0367] Although, the portions corresponding to the element regions arecontrolled so as to turn into an illumination-state corresponding to thedetermined brightness substantially at the same time in the embodimentsdescribed earlier, the portions corresponding to the element regions maybe controlled so as to turn into the illumination-state corresponding tothe determined brightness not substantially at the same time.

[0368] Further, a plurality of element regions capable of using variouspurposes are used for the hologram layer in the embodiments describedearlier, the hologram layer may not be formed with such regions capableof using various purposes. The hologram layer also may be formed withdedicated pattern regions correspondingly formed with the patterns ofthe interference fringes corresponding to predetermined beams. In such acase, a desired beam can be obtained by illuminating one of thededicated pattern regions.

[0369] The beam generators are applied to the following items such asplotting devices, barcode-readers, light pointers, turn signals for anautomobile and other vehicles, flash lights in the embodiments describedearlier. The usage of the beam generator is not limited to thesedevices, it can also applicable to an optical-pickup device and thelike, for example.

[0370] All the description in the earlier chapters may be applied tothis chapter unless otherwise they are not clearly applicable to thischapter. For example, the description on materials of the luminescentlayer 4, the anode vice 6 and that of the cathode 2, each composing thesurface light-emitting device, and the description on layered structureof the device with FIGS. 2 through 6, FIGS. 9 through 13, FIG. 17 andFIGS. 21 through 23 may also be applicable to this chapter.

[0371] Chapter 6

[0372]FIG. 31 is a sectional view for describing the structure of animage display device 90 using a surface light-emitting device accordingto another embodiment of the present invention. The image display device90 comprises stacked-layers formed of a cathode 2 acting as an electrodelayer, a luminescent layer 4 and an anode 6 forming another electrodelayer in that order, the stacked-layers being located adjacent to aglass substrate 8 forming a supporting body.

[0373] The cathode 2 is formed in a shape substantially corresponding tothe patterns of interference fringes of holograms. The cathode 2 forms ahologram layer. In other words, arrangement of portions 2 a, 2 b, 2 c, 2d and so on composing the cathode 2 correspond to the patterns ofinterference fringes of holograms.

[0374] Each of the portions 2 a, 2 b, 2 c, 2 d, and so on composing thecathode 2, and the anode 6 are connected to a control part 92. A DCvoltage is applied to between the portions 2 a, 2 b, 2 c, 2 d, and soon, and the anode 6 in accordance with the control of the control part92. All the components of the image display device 90 except for thecontrol part 92 form a surface light-emitting device. It is assumed thata three-dimensional object (for example, a miniature of a bus) is usedas the patterns of interference fringes of holograms. In other words,the structure of the image display device 90 except for using thehologram pattern of the three-dimensional object is almost the same tothat of the beam generator 40 shown in FIG. 14, for example.

[0375] Subsequently, the operation of the image display device 90 willbe described. Electric currents, each having a predetermined value flowrespectively through the portions 2 a, 2 b, 2 c, 2 d, and so oncomposing the cathode 2. In this way, portions between the portions 2 a,2 b, 2 c, 2 d, and so on composing the cathode 2 and the anode 6illuminate light out of the luminescent layer 4.

[0376] As described earlier, allocation of the portions 2 a, 2 b, 2 c, 2d, and so on corresponds to that of the interference fringes ofholograms of the three-dimensional object (see FIG. 16), and the currentvalues flowing through the portions 2 a, 2 b, 2 c, 2 d, and so onrespectively correspond to the information containing light intensity ofthe holograms of the three-dimensional object. As a consequence, thelight from the luminescent layer 4 under the three-dimensional mannerdisplays a holographic image Q corresponding to the three-dimensionalobject.

[0377] As described above, the cathode 2 is formed in a shapesubstantially corresponding to the hologram patterns of thethree-dimensional object. In this way, a part of the luminescent layer 4illuminate light correspondingly to the hologram patterns of thethree-dimensional object by flowing appropriate electric currentsthrough the cathode 2 and the anode 6.

[0378] As a consequence, the surface light-emitting device alone canplay both roles as the light source and the three-dimensional hologram.Consequently, the image display device 90 can be manufactured withcompact-profile and in reasonable cost by using the surfacelight-emitting device according to the present invention.

[0379] Although, the hologram patterns of the three-dimensional objectis formed as the hologram pattern in the above embodiment, the hologrampattern is not limited to the three-dimensional hologram pattern.Hologram pattern formed under pictures, planar drawings, characters andso on can be used as the hologram pattern of this embodiment. Further,combination of those can also be used as the hologram pattern.

[0380] The image display device according to the present invention canbe manufactured so as to selectively display a plurality of images suchas either of static images or dynamic images such as animations. In suchcase, the image display device shown in FIG. 22 may be used instead ofthe image display device 90 depicted in FIG. 31.

[0381] In this case, the TFT circuits 64 a, 64 b and so on are includedin the control part 92 shown in FIG. 31. The control part 92 is designedso as to provide information containing brightness corresponding to oneof the selected patterns out of more than one patterns of interferencefringes to the TFT circuits 64 a, 64 b and so on. A DC voltage isapplied between each of the portions 2 a, 2 b, 2 c, 2 d and so oncomposing the cathode 2 and the anode 6 in accordance with the controlof the control part 92. All the components of the image display device90 except for the control part 92 form the surface light-emittingdevice.

[0382] Three-dimensional objects can be reproduced in dynamic manner bysequentially reproducing a variety of hologram patterns corresponding toeach motion of the three-dimensional object, which is previouslyprepared.

[0383] In the embodiments described earlier, the hologram layer iscomposed of portions 2 a, 2 b, 2 c, 2 d and so on (element regions)forming the cathode 2, and brightness of the portions in the luminescentlayer 4 corresponding to each of the element regions is determinedcorrespondingly to the hologram pattern of the three-dimensional objectwhile illuminating the portions in the luminescent layer 4 in thepredetermined brightness.

[0384] In this way, a variety of holograms can be reproduced with justone image display device 90 by forming the element regions in a simpleshape capable of using various purposes while determining the brightnessof the portions in the luminescent layer 4 corresponding to each of theelement regions correspondingly to the selected hologram pattern. As aconsequence, three-dimensional objects can easily be reproduced indynamic manner in the previous case.

[0385] Moreover, pluralities of the element regions are substantiallydisposed in a matrix manner in the embodiment described earlier. In thisway, more variety of holograms can be reproduced with just one imagedisplay device 90 by using the element regions substantially disposed ina matrix manner capable of using various purposes. Consequently, morevariety of dynamic images can be reproduced in the previous case.

[0386] Information containing light intensity of the holograms isreproduced in accordance with brightness of the portions in theluminescent layer 4 where corresponding to the element regions. In thiscase, information containing phase of the holograms may be reproduced inaccordance with positions of the element regions corresponding to theportions under an illumination-state in the luminescent layer 4. In thisway, the holograms can be reproduced by varying the brightness of theportions in the luminescent layer 4 corresponding to the elementregions.

[0387] In addition, brightness of the portions in the luminescent layer4 corresponding to the element regions is respectively controlled byadjusting current values flowing through the portions in the luminescentlayer 4 corresponding to each of the element regions in this embodiment.In this way, information containing light intensity of the holograms caneasily be reproduced by just adjusting the current values. Consequently,reproduction of the holograms can easily be performed.

[0388] Further, the portions in the luminescent layer 4 corresponding tothe element regions are controlled so as to turn into anillumination-state corresponding to the determined brightnesssubstantially at the same time in the embodiment described above. Inthis way, reproduction of the holograms can be performed with certainty.

[0389] Still further, the portions in the luminescent layer 4corresponding to the element regions are capable of maintaining theirillumination-state and the corresponding portions under a row basis ofthe matrix are controlled so as to sequentially turn into theillumination-state corresponding to the determined brightness and tomaintain the illumination-state in the above-described embodiment.

[0390] In this way, the portions in the luminescent layer 4corresponding to the element regions are simultaneously turned into theillumination-state corresponding to the determined brightness at the endof scanning for all the lines by sequentially scanning the portions inthe luminescent layer 4 corresponding to the element regions under therow basis. Consequently, reproduction of the holograms can easily beperformed with certainty.

[0391] Yet further, the TFT circuits 64 a, 64 b, and so on forrespectively storing current values flowing through the luminescentlayer corresponding to each of the element regions are provided in theembodiment described earlier. In this way, the illumination-state ofeach portion in the luminescent layer 4 corresponding to each elementregion can be maintained by just storing the current values.Consequently, simultaneous illumination of the portions in theluminescent layer 4 corresponding to the element region can further becarried out easily.

[0392] The structure of the surface light-emitting device applicable tothe image display device capable of selectively displaying a pluralityof images is not limited to that depicted in FIG. 31. The surfacelight-emitting devices have shown in FIGS. 5A through 6B can also beapplied to the image display device. In addition, the surfacelight-emitting device depicted FIG. 32 can further be applied to suchimage display device.

[0393] In the surface light-emitting device depicted in FIG. 32, ashielding layer 21 forming the hologram layer is disposed at a positionoutside of the luminescent layer 4 and the light from the luminescentlayer 4 is emitted through the shielding layer 21.

[0394] Although, no specific limitations on the material of theshielding layer 21, for example, liquid crystal may be used therefor. Inthe case of using liquid crystal for the shielding layer, molecularalignment of the liquid crystal may be determined respectively toportions 21 a, 21 b, 21 c in the shielding layer 21 in accordance withhologram patterns. The reason of carrying out such step is to utilizethe feature of the liquid crystal in which light transmission varydepending upon molecular alignment thereto.

[0395]FIG. 33 is a view showing appearance of an IC card 94, an exampleof applying the image display device 90. In the IC card 94, amicrocomputer, a memory and peripherals are installed, the card 94, forexample, is used as a credit card and the like. Such IC card 94 is acontact type card and supply of its electric power and datacommunications are performed through a terminal 98.

[0396] The image display device 90 is installed in the IC card 94, thesurface of the surface light-emitting device composing the image displaydevice 90 is exposed from the surface of the card 94 as an image displaypart 96. The holographic image Q is displayed on the image display part96 in three-dimensional manner.

[0397] In this embodiment, the IC card 94 is characterized in using theimage display device 90. In this way, a lightweight, compact-profilewith reasonable price IC card capable of reproducing visual informationin three-dimensional manner can be realized. With the IC card 94, ahigher advertising-effect and difficulties in forgery can be expectedbecause visual information is reproduced in three-dimensional manner.

[0398] Although, the contact type IC card 94 is exampled as a card inthis embodiment, the present invention may also be applied to anon-contact type IC card. The usage of the image display deviceaccording to the present invention is not limited to IC cards.

[0399] Although, the surface light-emitting devices composed of aplurality of element regions disposed in a matrix manner and includingTFT circuits is exampled in the embodiment described above, the presentinvention can be applied to any surface light-emitting device except forthe device including the TFT circuits. The present invention can furtherbe applied to any surface light-emitting device except for the devicecomposed of a plurality of element regions disposed in a matrix manner.

[0400] Further, information containing light intensity of the hologramsis reproduced in accordance with the brightness of the portionscorresponding to the element regions in the devices described in theabove. The information may be reproduced by the number of the elementregions illuminating light under the condition that the portionscorresponding to the element regions are made to certain brightness.

[0401] Yet further, the portions corresponding to the element regionsare controlled so as to sequentially turn into the illumination-statecorresponding to the determined brightness and to maintain theillumination-state in the embodiments described earlier. Thecorresponding portions can be controlled so as to turn into anillumination-state corresponding to the determined brightnesssubstantially at the same time.

[0402] All the description in the earlier chapters may be applied tothis chapter unless otherwise they are not clearly applicable to thischapter. For example, the description on materials of the luminescentlayer 4, the anode vice 6 and that of the cathode 2, each composing thesurface light-emitting device, and the description on layered structureof the device with FIGS. 2 through 13, FIGS. 15 through 17, and FIGS. 22and 23 may also be applicable to this chapter.

[0403] Chapter 7

[0404] Luminescent layers composing surface light-emitting devices aremade of organic material(s) in all the chapters described earlier.Inorganic material(s) may also be used for the luminescent layer asdescribed above. There is no specific limitation on the inorganicmaterial(s) used for the luminescent layers, for example, asemi-conducting substance may be used. An example of using asemi-conducting substance for a luminescent layer composing a surfacelight-emitting device will be described hereunder.

[0405]FIG. 34 is a sectional view showing the overall structure of anexample of a surface-emitting laser device. The surface-emitting laserdevice depicted in FIG. 34 is a kind of semiconductor-laser devices inwhich light radiated from a luminescent layer 112 is emitted in adirection of Y1 as a laser beam after resonation of the radiated lightin a direction perpendicular to the luminescent layer 112 (shown as Y inthe drawing).

[0406] The laser device depicted in FIG. 34, roughly comprisesstacked-layers formed of a substrate 102 made of a semi-conductorsubstance, a Distributed Bragg Reflector located at a lower position(hereinafter referred to as lower DBR layer) 104, the luminescent layer112 made of a semiconductor substance, another Distributed BraggReflector located at an upper position (hereinafter referred to as upperDBR layer) 114 in that order.

[0407] The substrate 102 is made of a semi-conducting chemical compound,for example, an n type gallium and arsenic (Ga As).

[0408] The lower DBR layer 104, for example, also has stacked-layers inwhich pluralities of pairs (a total of thirty four (34) pairs in thisembodiment) each including two kinds of thin films both having adifferent refractive index such as quarter of A thin film (thin filmseach having an equivalent thickness of λ/4 of wavelength of laser beamemitted from the laser, the thin films hereinafter referred to as λ/4thin films). As for materials for forming these two λ/4 thin films, forexample, a chemical compound of aluminum and arsenic (Al As), anotherchemical compound of aluminum, gallium and arsenic (Al Ga As) are used.In order to provide conductivity to these λ/4 thin films composing thelower DBR layer 104, n-type impurities are added to the films.

[0409] The upper DBR layer 114 also has almost the same structures tothat of the lower DBR layer 104. However, P-type impurities are added tothe two kinds of λ/4 thin films composing upper DBR layer 114 in orderto provide conductivity thereto. A total of twenty two (22) pairs of theλ/4 thin films are included in the upper DBR layer 114 in thisembodiment.

[0410] The luminescent layer 112 forming a composite semi-conductingsubstance comprises a stacked-layer formed of an n-clad layer 106forming a first semi-conductor layer, a Multi-Quantum Well layer(hereinafter referred to as MQW layer) 108, a p-clad layer 110 forming asecond semi-conductor layer in that order.

[0411] The n-clad layer 106, for example, is made of a semi-conductingchemical compound of Al Ga As adding n-type (first conductive type)impurities therein. The p-clad layer 110, for example, is made of asemi-conducting chemical compound of Al Ga As adding p-type (secondconductive type) impurities therein. Both the n-clad layer 106 and thep-clad layer 110 are respectively formed in a thickness of approximately0.1 μm, for example.

[0412] The MQW layer is a semiconductor layer having double-layerstructure made of Al Ga As/Ga As with no impurities. The MQW layer 108is also referred to as an active layer and is formed in a thickness ofapproximately 6 nano-meters, for example.

[0413] The MQW layer 108, very thin in its thickness and situatedadjacent to the boundary between the p-clad layer 110 and the n-claylayer 106 illuminates when a direct current is applied to thesurface-emitting laser device having such structure by the DC powersource 10. The light illuminated from the MQW layer 108 is reflected bythe λ/4 thin films composing both the lower DBR layer 104 and the upperDBR layer 114, and the reflected light is resonated in the direction ofY thereby, both the lower DBR layer 104 and the upper DBR layer 114being located at both sides of the luminescent layer 112. The resultinglaser beam by the resonation is emitted in the direction of Y1 throughthe upper DBR layer 114.

[0414] The upper DBR layer 114 comprises a plurality of reflectingmirrors while functioning a part of an electrode for applying anelectric current to the p-clad layer 110. The lower DBR layer 104comprises a plurality of reflecting mirrors while functioning as a partof an electrode for providing a electric current to the n-clad layer106.

[0415]FIG. 35 is a view for describing the structure of another beamgenerator 100 forming an optical-input/output device using the surfacelight-emitting device according to far another embodiment of the presentinvention. The beam generator 100 uses the surface-emitting laser devicedepicted in FIG. 34.

[0416] In the beam generator 100, a lower DBR layer 104, a luminescentlayer 112, an upper reflecting mirror portion 115 forming the hologramlayer, an insulating part 116, and an aluminum wire 118 are formed on asubstrate 102.

[0417] The structure of the substrate 102, the lower DBR layer 104, andthe luminescent layer 112 is similar to that of these included in thesurface-emitting laser device shown in FIG. 34.

[0418] The upper reflecting mirror portion 115 includes a plurality ofportions 115 a, 115 b, and so on. The portions 115 a, 115 b and so oncorresponds to a part of the upper DBR layer 114 shown in FIG. 34. Aswill be subsequently described, the insulating part 116, however, may beformed by making other part of the upper DBR layer 114 shown in FIG. 34as an insulated part. The portions 115 a, 115 b, and so on respectivelyforms element region (element electrode).

[0419]FIG. 36 is a plan view for describing the structure of the beamgenerator 100. As apparent form FIG. 36, all the portions 115 a, 115 b,and so on are formed identical in shape (in this embodiment, round shapein plane) and are allocated in matrix manner.

[0420] Among the portions 115 a, 115 b, and so on are insulated oneanother with the insulating part 116.

[0421] The aluminum wirings 118 each having doughnut shape are disposedon the boundaries between the portions 115 a, 115 b and so on and theinsulating part 116, the boundaries being exposed from the surface. Inthis way, lower ends of the aluminum wirings 118 are electricallyconnected to upper ends located peripheries of the portions 115 a, 115 band so on.

[0422] The portions 115 a, 115 b and so on composing the mirror portion115 are respectively connected to a control part 120 via the wirings118. Further, the substrate 102 is connected to control part 120 aswell. A DC voltage is applied between both the portions 115 a, 115 b andso on composing the upper reflecting mirror portion 115 and thesubstrate 102 in accordance with the control of the control part 120. Inother words, a laser beam is emitted in the direction Y1 from anydesired portions 115 a, 115 b and so on in accordance with the controlof the control part 120. All the components of the beam generator 100except for the control part 120 form a surface light-emitting device.

[0423] Subsequently, a manufacturing method of a surface light-emittingdevice included in the beam generator 100 will be described withreference to FIGS. 37A through 38B. At first, the lower DBR layer 104,the luminescent layer 112 (including the n-clad layer 106, the MQW layer108, and the p-clad layer 110), and the upper DBR layer 114 are formedon the substrate 102 in that order with epitaxial process and the likeas shown in FIG. 37A.

[0424] Substantially, a silicon oxidation layer 124 is formed on theupper DBR layer 114 as shown in FIG. 37B. The silicon oxidation layer124 is then patterned so as to cover the portions to be turned into theportions 115 a, 115 b, and so on. Thereafter, proton is implantedionically into the upper DBR layer 114 by using the resulting siliconoxidation layer 124 as a mask.

[0425] Next, the resulting silicon oxidation layer 124 is removed asshown in FIG. 38A. The portions implanting proton lose theirconductivity so that these portions are turned into the insulating part116. The portions not implanting proton, on the other hand, not losetheir conductivity. The portions not losing their conductivity areturned into the upper reflecting mirror portion 115. In this way, themirror portion 115 (hologram portion) having a desired pattern (apattern in matrix manner in this embodiment) can easily be formed.

[0426] Subsequently, the aluminum wirings 118 are wired as shown in FIG.38B. AS described earlier, the aluminum wirings 118 each having doughnutshape are disposed on the boundaries between the portions 115 a, 115 band so on and the insulating part 116, the boundaries being exposed fromthe surface (see FIG. 36). By performing these steps, the surfacelight-emitting device used for the beam generator 100 is manufactured.

[0427]FIG. 39 is a sectional view for describing the structure ofanother beam generator 130 forming an optical-input/output device usingthe surface light-emitting device according to another embodiment of thepresent invention. The beam generator 130 uses the surface-emittinglaser device depicted in FIG. 34 and has the similar structure to thatof the beam generator 100 shown in FIG. 35.

[0428] However, the beam generator 130 shown in FIG. 39 differs from thebeam generator 100 shown in FIG. 35 in view of forming an insulatingpart 132 with other material, for example, polyimide.

[0429] In order to fabricate the beam generator 130 shown in FIG. 39,the upper DBR layer 114 is etched so as to leave the portions 115 a, 115b and so on composing the upper reflecting mirror portion 115 aftercarrying out the step shown in FIG. 37A. Thereafter, insulationmaterial(s) such as polyimide is applied so as to fulfill the spacesformed among the portions 115 a, 115 b, and so on forming the mirrorportion 115. The step for disposing the aluminum wirings 118 is alsocarried out similar to the manufacturing steps of the beam generator 100shown in FIG. 35.

[0430]FIG. 40 is a sectional view for describing the structure ofanother beam generator 140 forming an optical-input/output device usingthe surface light-emitting device according to another embodiment of thepresent invention. The beam generator 140 also uses the surface-emittinglaser device depicted in FIG. 34 and has the similar structure to thatof the beam generator 100 shown in FIG. 35.

[0431] However, the beam generator 140 shown in FIG. 40 differs from thebeam generator 100 shown in FIG. 35 in view of the followings: 1)remaining the upper DBR layer 114 as it is, 2) providing a shieldinglayer 142 having a shape corresponding to interference fringes ofholograms so as to cover the shielding layer 142, and 3) emitting alaser beam from the spaces formed among the shielding layer 142.

[0432] Further, a DC power supply 10 is used instead of the control partin the beam generator 140 shown in FIG. 40. In other words, laser beamshaving desired shape can be realized by emitting a laser beam from thespaces formed among the shielding layer 142 out of the generated laserbeam as a result of applying a DC voltage between the upper DBR layer114 and the substrate 102 in the beam generator 140 shown in FIG. 40.

[0433] In this way, desired laser beams and the like can be obtained byjust forming the shielding layer 142 in the shape corresponding to theinterference fringes of the holograms without providing the control partas well as complicated wirings.

[0434] In this embodiment, electric resistance of the upper most planeof the upper DBR layer is lowered, and a cable from the power supply 10is connected to the uppermost plane thus lowered in electric resistance.It is preferred to design in this way because electric potential is instable all over the upper DBR layer 114.

[0435] As described above, the luminescent layer 112 comprise astacked-layer formed of the n-clad layer 106, the MQW layer 108, thep-clad layer 110 in that order, and the light radiated from the MQWlayer 108 is emitted in a direction perpendicular to the luminescentlayer 112 as a laser beam after resonation of the radiated light in theembodiments described in this chapter.

[0436] In this way, it is possible to realize a surface light-emittingdevice much suitable for reproduction of holograms by using the emittedlaser beams. Moreover, a desired illumination pattern may easily beobtained by emitting the laser beam in the direction perpendicular tothe luminescent layer 112. In other words, a desired hologram patterncan easily be obtained. Further, laser oscillation can easily beperformed by employing a semi-conducting substance having a high heatresistance for the luminescent layer 112.

[0437] Both the lower DBR layer 104 and the upper DBR layer 114 (or theupper reflecting mirror portion 115) each provided so as to interposethe luminescent layer 112 and having reflecting planes substantiallyparallel to the luminescent layer 112 are included in the generators inthe embodiments described in this chapter, and light radiated from theluminescent layer 112 is resonated in a direction perpendicular to theluminescent layer 112.

[0438] As a consequence, the volume of areas interposed between thelower DBR layer 104 and the upper DBR layer 114 (or the upper reflectingmirror portion 115) can be reduced. In this way, the threshold value forinitiating the laser oscillation can be lowered. In other words, asurface light-emitting device and the like with low-power consumptioncan be realized. In addition, the upper DBR layer 114 can further bepatterned in detail. In other words, hologram pattern with finerpatterning may easily be obtained.

[0439] The surface-emitting laser device comprising a plurality ofreflecting mirrors for resonating the generated light in the directionsubstantially perpendicular to the luminescent layer in the embodimentsdescribed in this chapter. The usage of the present invention is notlimited to the surface-emitting laser device. The present invention mayalso be applicable to a surface-emitting laser device comprising tworeflecting mirrors one of which is used for resonating the generatedlight beam in the direction substantially parallel to the luminescentlayer and the other one is used for emitting the resulting laser beamresonated with the former mirror in a direction substantiallyperpendicular to the luminescent layer. The semi-conducting material(s)conductive material(s), insulation material(s) composing the luminescentlayer are not limited to those mentioned in the embodiments describedearlier.

[0440] The shape of the luminescent layer is not limited to thosedescribed in the embodiments described earlier.

[0441] The surface-emitting laser devices emitting laser beams by usingthe luminescent layer made of a semi-conducting substance are describedin the embodiments described in this chapter. The present invention isnot limited to semi-conducting substance. A surface-emitting laserdevice emitting laser beams by using the luminescent layer made ofinorganic material(s) other than semi-conducting substance and/ororganic material(s) and the like may also be applicable to the presentinvention. For example, laser beams may be obtained by asurface-emitting laser device using the luminescent layer made oforganic material(s) instead of semi-conducting substance.

[0442] All the descriptions in each of the chapters described earlierare applied to this chapter unless otherwise they are not clearlyapplicable to this chapter. The surface-emitting laser device describedin this chapter (laser devices emitting laser beams in a directionsubstantially perpendicular to the luminescent layer) may also be usedas the light source of the device/beam generators and the like in thechapters described earlier. In other words, the surface-emitting laserdevices described in this chapter can be applicable to the surfacelight-emitting devices, the beam generators, the device for monitoringreflected light, the plotting devices, the light scanning and readingdevice, image display devices, and the IC cards described earlierchapters.

[0443] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is substantiallyformed in a shape corresponding to a pattern of interference fringes ofa hologram.

[0444] In this way, the luminescent layer emits light corresponding tothe patterns of hologram as a result of applying a voltage to theelectrodes. As a consequence, the surface light-emitting device alonecan play both roles as the light source and the optical elements bymaking the patterns of interference fringes of holograms with thehologram patterns of optical elements such as lens, for example. Inother words, a lightweight and compact-profile optical input/outputdevice with reasonable price can be realized by using the surfacelight-emitting device according to the present invention.

[0445] The shape corresponding to the patterns of interference fringesof holograms can be formed easily and accurately because both theelectrodes are made of easy-to-form material.

[0446] The surface light-emitting device according to the presentinvention is characterized in that, a pair of electrode layersinterposing the luminescent layer therebetween,

[0447] and wherein one of the electrode layers is formed as atransparent electrode layer substantially having the shape correspondingto the pattern of interference fringes of the hologram,

[0448] and wherein the light from the luminescent layer is emittedthrough said transparent electrode.

[0449] In this way, the light emitted correspondingly to the patterns ofinterference fringes from the luminescent layer comes out externallythrough the transparent electrode formed in a shape substantiallycorresponding to the patterns of interference fringes as a result ofapplying a voltage between the electrodes. Consequently, lightreproduced with high fidelity to the patterns of interference fringesmay be obtained.

[0450] The surface light-emitting device according to the presentinvention is characterized in that, a supporting member is provided to aposition outside of the other one of the electrode layers,

[0451] and wherein the light from the luminescent layer is emittedthrough said one electrode layer.

[0452] In this way, the light from the luminescent layer can be emittedexternally without passing through the supporting member. As aconsequence, the light comes out without much degradation of the lightamount.

[0453] The surface light-emitting device according to the presentinvention is characterized in that, a supporting member havingtransparency is provided to a position outside of said one electrodelayer,

[0454] and wherein the light from the luminescent layer is emittedthrough said one electrode layer and the supporting member.

[0455] Consequently, the transparent electrode formed in the patterns ofinterference fringes can be provided on the supporting member afterdisposing the supporting member prior to providing the transparentelectrode thereon. As a result, it is possible to obtain a shapecorresponding to the pattern of interference fringes of the hologrameasily and more precisely.

[0456] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0457] and wherein one of the electrode layers is formed in a shapesubstantially corresponding to a pattern of interference fringes of ahologram while forming the other one of the electrode layers as atransparent electrode layer,

[0458] and wherein light from the luminescent layer is emitted throughthe other electrode layer.

[0459] In this way, the electrode layers formed in a shape correspondingto the patterns of interference fringes not necessary to be transparentelectrodes. As a consequence, an easy-to-form material for theelectrodes can be selected. In other words, it is possible to obtain ashape corresponding to the pattern of interference fringes of thehologram easily and more precisely.

[0460] The surface light-emitting device according to the presentinvention is characterized in that, a supporting member havingtransparency is provided to a position outside of the other electrodelayer,

[0461] and wherein the light from the luminescent layer is emittedthrough the other electrode layer and the supporting member.

[0462] Consequently, the surface light-emitting device can easily befabricated by using an element including transparent electrodes formedon the supporting member having transparency and readily available.

[0463] The surface light-emitting device according to the presentinvention is characterized in that, a shielding layer formed in a shapesubstantially corresponding to a pattern of interference fringes of ahologram is provided at a position outside of the luminescent layer,

[0464] and wherein the light from the luminescent layer is emittedthrough the shielding layer.

[0465] In this way, light corresponding to the patterns of interferencefringes can easily be emitted by using the shielding layer as a mask forthe light emitted from the luminescent layer. As a consequence, thesurface light-emitting device alone can play both roles as the lightsource and the optical elements by making the patterns of interferencefringes of holograms with the hologram patterns of optical elements suchas lens, for example. In other words, a lightweight, compact-profileoptical-input/output device with reasonable price capable of emittinglight can be realized easily by using the surface light-emitting device.

[0466] Further, the shielding layer may be formed with an easy-to-formmaterial because not many restrictions exist on the material therefor.Consequently, the shape corresponding to the patterns of interferencefringes of holograms can be formed easily and accurately.

[0467] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0468] and wherein one of the electrode layers is formed as atransparent electrode layer while providing the shielding layer at aposition outside of said one electrode layer.

[0469] In this manner, the entire portion of the luminescent layerilluminates by applying a voltage between a pair of the electrode, sothat a part of the resulting light can be emitted through the shieldinglayer 20 formed corresponding to the patterns of interference fringes asa mask. Consequently, light reproduced with high fidelity to thepatterns of interference fringes may be obtained.

[0470] The surface light-emitting device according to the presentinvention is characterized in that, a supporting member havingtransparency is provided to a position outside of the shielding layer,

[0471] and wherein the light from the luminescent layer is emittedthrough said one electrode layer, the shielding layer and the supportingmember.

[0472] In this way, the shielding layer formed in the patterns ofinterference fringes can be provided on the supporting member afterdisposing the supporting member prior to providing the shielding layerthereon. As a result, it is possible to obtain a shape corresponding tothe pattern of interference fringes of the hologram easily and moreprecisely.

[0473] The surface light-emitting device according to the presentinvention is characterized in that, an uneven transparent layer formedunevenly in thickness corresponding to a pattern of interferencefringes, is disposed at a position outside of the luminescent layer,

[0474] and wherein the light from the luminescent layer is emittedthrough the uneven transparent layer.

[0475] In this way, light corresponding to the patterns of interferencefringes can easily be emitted by using the uneven transparent layer as amask for the light emitted from the luminescent layer. As a consequence,the surface light-emitting device alone can play both roles as the lightsource and the optical elements by making the patterns of interferencefringes of holograms with the hologram patterns of optical elements suchas lens, for example. In other words, a lightweight, compact-profileoptical-input/output device with reasonable price capable of emittinglight can be realized easily by using the surface light-emitting device.

[0476] Further, the uneven transparent layer may be formed with aneasy-to-form material because not many restrictions exist on thematerial therefor. Consequently, the shape corresponding to the patternsof interference fringes of holograms can be formed easily andaccurately.

[0477] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0478] and wherein one of the electrode layers is formed as atransparent electrode layer while providing the uneven transparent layerat a position outside of said one electrode layer.

[0479] In this manner, the entire portion of the luminescent layerilluminates by applying a voltage between a pair of the electrode, sothat the resulting light can be emitted through the uneven transparentlayer formed unevenly in thickness substantially corresponding to thepattern of the interference fringes. Consequently, light reproduced withhigh fidelity to the patterns of interference fringes may be obtained.

[0480] The surface light-emitting device according to the presentinvention is characterized in that, the uneven transparent layer is asupporting member having transparency,

[0481] and wherein the light from the luminescent layer is emittedthrough said one electrode layer and the supporting member.

[0482] As a consequence, a shape corresponding to the patterns ofinterference fringes can easily and accurately be obtained by justforming convex/concave patterns corresponding to the patterns ofinterference fringes on the surface of the supporting member havingtransparency.

[0483] The surface light-emitting device according to the presentinvention is characterized in that, the uneven transparent layer is apassivation layer having transparency,

[0484] and wherein the light from the luminescent layer is emittedthrough said one electrode layer and the passivation layer.

[0485] As a consequence, a shape corresponding to the patterns ofinterference fringes can easily and accurately be obtained by justforming convex/concave patterns corresponding to the patterns ofinterference fringes on the surface of the passivation layer havingtransparency.

[0486] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0487] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0488] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0489] The surface light-emitting device according to the presentinvention is characterized in that, molecular alignment of organicmaterial is in parallel to the electrodes. This permits strongerlight-emitting intensity even when a low voltage is applied.

[0490] The beam generator according to the present invention ischaracterized in that, a predetermined beam is generated by utilizingthe surface light-emitting device. In this way, the beam generator canbe made as a lightweight, compact-profiled, yet reasonable priceddevice.

[0491] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to the patterns of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path,

[0492] and wherein the light from the luminescent layer directed toother than the predetermined optical path is emitted to a directionother than the predetermined optical path.

[0493] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0494] As a consequence, localization of an imaginary light sourcecreated by reflection of the lights directed to the backside to aposition other than that of the luminescent part may be avoided bypermitting the travel of most of the lights go to the backside from theluminescent layer in the backward-direction. Consequently, the lightsource can keep its substantial optical depth narrow. It is, therefor,possible to obtain the lights suitable for reproduction of holograms.

[0495] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0496] and wherein both the electrode layers are formed as transparentelectrode layers.

[0497] In this way, the light from the luminescent layer directed toother than the predetermined optical path may be emitted in thatdirection by forming both the electrode layers as transparent electrodelayers.

[0498] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to a pattern of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path,

[0499] and wherein the light from the luminescent layer directed toother than the predetermined optical path is reflected and incorporatedwith another light from the luminescent layer directed to thepredetermined optical path so as to intensify a resulting light.

[0500] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0501] The resulting light having a higher intensity can be obtained byreflecting the light from the luminescent layer directed to other thanthe predetermined optical path and incorporating the reflected lightwith another light from the luminescent layer directed to thepredetermined optical path so as to intensify a resulting light. Inother words, the light source much suitable for the reproduction ofholograms can be obtained.

[0502] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0503] and wherein one of the electrode layers is formed as atransparent electrode layer while forming the other one of electrodelayers as an electrode capable of reflecting light on its surface,

[0504] and wherein the light from the luminescent layer that is directedto said one electric layer and the light reflected on the surface of theother electrode layer is incorporated and emitted.

[0505] In this way, both the light from the luminescent layer directedto other than the predetermined optical path as a result of reflectionon the surface and another light from the luminescent layer directed tothe predetermined optical path can easily be incorporated and emitted byforming one of the electrode layers as the transparent electrode layerwhile forming the other one of electrode layers as the electrode capableof reflecting light on its surface.

[0506] The surface light-emitting device according to the presentinvention is characterized in that, an optical distance u1 from aluminescent part of the luminescent layer to the surface of the otherelectrode layer is defined as the following equation;

u1≈(2n−1)λ/4

[0507] wherein “n” is a positive integer, and “λ” represents to awavelength of a desired light emitted from the device.

[0508] In this way, phase of reflected light of the light from theluminescent layer directed to other than the predetermined optical pathand that of the light emitted therefrom being directed to thepredetermined optical path are nearly matched. It is, therefore,possible to emit light suitable for the reproduction of holograms.

[0509] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to a pattern of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path,

[0510] and wherein the light from the luminescent layer is resonated andemitted.

[0511] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0512] The device fabricated under the structure described above canobtain monochromatic radiation having a high intensity effectively witha simple structure. Also, light having a high directivity can beobtained with the device as well. Lights having similar phase canfurther be obtained. In addition, it is possible to provide a surfacelight-emitting device realizing the light source suitable forreproduction of holograms.

[0513] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0514] and wherein one of the electrode layers is formed as atransparent electrode layer while forming the other one of electrodelayers as an electrode capable of reflecting light on its surface,

[0515] and wherein dielectric reflective layer not less than one isprovided to a position outside of said one electrode layer,

[0516] and wherein the light is resonated between the surface of theother electrode layer and a reflective plane of the dielectricreflective layer, and is then emitted therefrom.

[0517] In this way, the light from the luminescent layer can easily beemitted after resonation thereof by providing both the electrodescapable of reflecting light on its surface and the dielectric reflectivelayer not less than one.

[0518] The surface light-emitting device according to the presentinvention is characterized in that, wherein an optical distance u2 fromthe reflective plane of the dielectric reflective layer to the surfaceof the other electrode layer is defined as the following equation;

U2≈nλ/2

[0519] wherein “A” represents a wavelength of a desired light emittedfrom the device.

[0520] In this way, the light emitted from the luminescent layer canfurther be emitted effectively as a result of performing effectiveresonation.

[0521] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0522] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0523] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0524] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to the patterns of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path,

[0525] and wherein the hologram layer is formed alone with a partlocated periphery of interference fringes of the hologram.

[0526] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0527] The hologram layer can be formed with only the part where isnarrow in distance between the fringes by using the peripheral part ofthe interference fringes of the holograms.

[0528] The directivity of lights after passing through holograms HGreceives much influence of both the conditions of the lights beforepassing therethrough and the distance between the fringes. However, moreinfluence of the distance than that of the condition of the lightsbefore passing through the hologram layer may be expected at the partwhere is narrow in distance.

[0529] In this way, it is assumed that the light directivity can becontrolled in accordance with the distance of the fringes regardless ofthe conditions of the lights before passing through the hologram layerif the hologram layer is formed with the part where is narrow indistance between the fringes alone.

[0530] In other words, a hologram layer much suitable for reproductionof holograms may be realized.

[0531] The surface light-emitting device according to the presentinvention is characterized in that, hologram layer formed substantiallycorresponding to a pattern of interference fringes of a hologram isformed as a layer one of related to light emission and provided on thepredetermined optical path,

[0532] and wherein the hologram layer includes a light-pattern and adark-pattern,

[0533] and wherein a width of the light-pattern is substantially formedin a range of a wavelength of the light or less than said range.

[0534] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0535] The light-pattern very narrow in width can be realized by formingthe width of the light-pattern substantially equal to or less than thewavelength of the light.

[0536] The light directivity of lights after passing through hologramsreceives much influence of both the conditions of the lights beforepassing therethrough and the width of the light-patters. However, notmuch influence is expected on the conditions of the lights beforepassing therethrough if the width of the light-patterns is in narrow.

[0537] As a consequence, it is considered that the light directivity canbe controlled regardless of the conditions of the lights before passingthrough the hologram layer if the hologram layer is formed so as tonarrow the width of the light-pattern. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0538] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is formed alonewith a part located periphery of interference fringes of the hologram.In this way, it is possible to realize a hologram layer much suitablefor the reproduction of holograms.

[0539] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming the electrode in a shape substantially correspond to the patternof the interference fringes.

[0540] In this way, a shape corresponding to the patterns ofinterference fringes of holograms can be formed easily and accurately byforming the hologram layer with easy-to-form electrodes.

[0541] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming the luminescent layer in a shape substantially correspond to thepattern of the interference fringes.

[0542] Light reproduced with high fidelity to the patterns ofinterference fringes may be obtained by utilizing the luminescent layeritself as the hologram layer.

[0543] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming a shielding layer in a shape substantially correspond to thepattern of the interference fringes at a position outside of theluminescent layer, and wherein the light from the luminescent layer isemitted through the shielding layer.

[0544] In this way, a hologram layer made of an easy-to-form materialcan be formed by using the shielding layer with not many restrictionsexist on its material as the hologram layer. As a consequence, a shapecorresponding to the patterns of interference fringes of holograms canbe formed easily and accurately.

[0545] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming an uneven transparent layer formed unevenly in thicknesssubstantially corresponding to the pattern of the interference fringesat a position outside of the luminescent layer,

[0546] and wherein the light from the luminescent layer is emittedthrough the uneven transparent layer.

[0547] In this way, a hologram layer made of an easy-to-form materialcan be formed by using the uneven transparent layer with not manyrestrictions exist on its material as the hologram layer. As aconsequence, a shape corresponding to the patterns of interferencefringes of holograms can be formed easily and accurately.

[0548] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0549] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer much suitable for reproductionof holograms by using organic materials therefor.

[0550] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0551] The beam generator according to the present invention ischaracterized in that, generating a predetermined beam with said surfacelight-emitting device. In this way, a lightweight, compact-profile beamgenerator with reasonable price can further be realized.

[0552] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to the pattern of the interference is formedas a layer one of related to light emission and provided on thepredetermined optical path,

[0553] and wherein the hologram layer includes a light-pattern and adark-pattern,

[0554] and wherein the light-pattern is formed in a fixed width,

[0555] and wherein information containing light intensity of theholograms is reproduced in accordance with brightness of a portiongenerating light where corresponding to the light-pattern.

[0556] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0557] Further, information containing phase of the holograms may bereproduced by allocating pattern elements as a result of forming thedevice as the followings. 1) forming the light-pattern in a fixed width,and 2) reproducing information containing light intensity of thehologram by the brightness of the portions corresponding to the elementregions.

[0558] In this way, the hologram layer can be formed by just allocatingeach of the element regions having a fixed width. In other words,formation of the hologram layer may easily be carried out.

[0559] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming the electrode in a shape substantially correspond to the patternof the interference fringes.

[0560] In this way, a shape corresponding to the patterns ofinterference fringes of holograms can be formed easily and/accurately byforming the hologram layer with easy-to-form electrodes.

[0561] The surface light-emitting device according to the presentinvention is characterized in that, wherein the hologram layer iscomposed by forming the luminescent layer in a shape substantiallycorrespond to the pattern of the interference fringes.

[0562] Light reproduced with high fidelity to the patterns ofinterference fringes may be obtained by utilizing the luminescent layeritself as the hologram layer.

[0563] The surface light-emitting device according to the presentinvention is characterized in that, brightness of the portion wherecorresponding to the light-pattern is controlled by adjusting a currentvalue flowing through the luminescent layer.

[0564] In this way, light intensity of the holograms can easily bereproduced by adjusting the current value. As a consequence,reproduction of the holograms may easily be carried out.

[0565] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byproviding a shielding layer formed in a shape substantiallycorresponding to a pattern of interference fringes of a hologram at aposition outside of the luminescent layer,

[0566] and wherein the light from the luminescent layer is emittedthrough the shielding layer.

[0567] In this way, a hologram layer made of an easy-to-form materialcan be formed by using the shielding layer with not many restrictionsexist on its material as the hologram layer. As a consequence, a shapecorresponding to the patterns of interference fringes of holograms canbe formed easily and accurately.

[0568] The surface light-emitting device according to the presentinvention is characterized in that, the light-pattern is substantiallyformed in a width, a range of which is one of wavelength of the light orless than said range.

[0569] In this way, the light-pattern very narrow in width can berealized. The light directivity of lights after passing throughholograms receives much influence of both the conditions of the lightsbefore passing therethrough and the width of the light-patterns.However, not much influence is expected on the conditions of the lightsbefore passing therethrough if the width of the light-patterns is innarrow.

[0570] As a consequence, it is considered that the light directivity canbe controlled regardless of the conditions of the lights before passingthrough the hologram layer if the hologram layer is formed so as tonarrow the width of the light-pattern. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0571] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0572] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0573] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0574] The beam generator according to the present invention ischaracterized in that, generating a predetermined beam with said surfacelight-emitting device. In this way, a lightweight, compact-profile beamgenerator with reasonable price can further be realized.

[0575] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to a pattern of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path, and wherein the device isfabricated so that the light once emitted through the optical pathreturns through the hologram layer as a reflected light.

[0576] In this way, the surface light-emitting device alone can playroles as the light source, lens and the half-mirror by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device outputtinglight while using the reflected light as incident light with reasonableprice can be realized by using the surface light-emitting deviceaccording to the present invention.

[0577] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer includes alight-pattern and a dark-pattern,

[0578] and wherein a portion generating light where corresponding to thelight-pattern is formed so that light travels in a forward-direction tothe optical path but not proceeds in a backward-direction thereto, andwherein a portion not generating light where corresponding to thedark-pattern is formed so that light proceeds in a backward-direction tothe optical path.

[0579] The light emitted from the light-pattern only travels in theforward-direction and reflected by an object. The reflected light passesthrough the dark-pattern and travels to the backward-direction of theoptical path. As a consequence, the optical input/output deviceoutputting light while using the reflected light as incident light withcompact-profile and in reasonable cost can easily be realized bycomposing the hologram layer with both the light-pattern and thedark-pattern.

[0580] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is the hologram layer.In this way, a shape corresponding to the patterns of interferencefringes of holograms can be formed easily and accurately by forming thehologram layer with easy-to-form electrodes.

[0581] The surface light-emitting device according to the presentinvention is characterized in that, the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween,

[0582] and wherein one of the electrode layers disposed at a positionbehind the optical path is formed as the hologram layer,

[0583] and wherein the other one of electrode layers disposed at aposition in front of the optical path is formed as a transparentelectrode.

[0584] In this way, the electrode layers formed in a shape correspondingto the patterns of interference fringes not necessary to be transparentelectrodes. As a consequence, an easy-to-form material for theelectrodes can be selected. In other words, it is possible to obtain ashape corresponding to the pattern of interference fringes of thehologram easily and more precisely.

[0585] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is thehologram layer.

[0586] In this way, light reproduced with high fidelity to the patternsof interference fringes may be emitted to the forward-direction byutilizing the luminescent layer itself as the hologram layer. The lightreflected may also be transmitted correspondingly to the dark-patternwith fidelity in the backward-direction.

[0587] The surface light-emitting device according to the presentinvention is characterized in that, a non-light transmission layerformed in a shape corresponding to the light-pattern, is disposed at aposition back-side of said one electrode layer situated behind theoptical path.

[0588] In this way, leakage of the light from the light-pattern in thebackward-direction may certainly be avoided. Under the circumstances,any electrode material(s) for the electrode having superior capabilitiesof electric charge-injection and formability may be selected withoutconcerning the capability of light shielding thereof.

[0589] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0590] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0591] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0592] The device for monitoring reflected light according to thepresent invention is characterized in that, device for monitoringreflected light using an optical sensor is disposed at a position behindthe hologram layer.

[0593] In this way, a lightweight, compact-profile, low-cost monitoringdevice can be realized.

[0594] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to a patterns of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path,

[0595] and wherein a plurality of element regions are included in thehologram layer,

[0596] and wherein brightness of portions corresponding to the elementregions is determined in accordance with the patterns of theinterference fringes,

[0597] and wherein the corresponding portions are controlled so as toturn into an illumination-state corresponding to the determinedbrightness substantially at the same time.

[0598] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example. In other words, alightweight and compact-profile optical input/output device withreasonable price can be realized by using the surface light-emittingdevice according to the present invention.

[0599] Further, reproduction of the holograms can be performed withcertainty because the portions corresponding to the element regions arecontrolled so as to turn into an illumination-state corresponding to thedetermined brightness substantially at the same time.

[0600] In addition, the element regions may be formed in a simple shape,and information containing light intensity of the holograms can bereproduced in accordance with the brightness of the element regionsbecause the hologram layer includes a plurality of element regions andthe brightness of portions corresponding to the element regions isdetermined in accordance with the patterns of the interference fringes.By forming the device in this way, information containing phase of theholograms may be reproduced in accordance with positions of the elementregions. Consequently, formation of the hologram layer may easily becarried out.

[0601] The surface light-emitting device according to the presentinvention is characterized in that, the portions corresponding to theelement regions are capable of maintaining the illumination-state,

[0602] and wherein the corresponding portions are controlled so as tosequentially turn into the illumination-state corresponding to thedetermined brightness and to maintain the illumination-state.

[0603] In this way, the corresponding portions are simultaneously turnedinto an illumination-state corresponding to the determined brightness atthe end of scanning for all the lines by sequentially scanning thecorresponding portions. Consequently, reproduction of the holograms caneasily be performed with certainty.

[0604] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming the electrode with element electrodes substantially forming saidpluralities of element regions.

[0605] The shape of the element regions may easily be reproducedcorrectly by forming the element regions with easy-to-form electrodes.

[0606] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed byforming the luminescent layer with element luminescent layerssubstantially forming said pluralities of element regions.

[0607] Light reproduced with high fidelity to the patterns of theelement regions may be obtained by utilizing the luminescent layeritself as the element regions.

[0608] The surface light-emitting device according to the presentinvention is characterized in that, brightness of portions correspondingto the element regions is respectively controlled by adjusting currentvalues flowing through the luminescent layer corresponding to each ofthe element regions.

[0609] In this way, information containing light intensity of theholograms can be reproduced by adjusting the current values.Consequently, reproduction of the holograms can easily be performed.

[0610] The surface light-emitting device according to the presentinvention is characterized in that, a storing part for storing currentvalues flowing through the luminescent layer which correspond to each ofthe element regions respectively, is provided.

[0611] In this way, illumination-state of each portion corresponding toeach element region can be maintained by just storing the currentvalues. Consequently, simultaneous illumination corresponding to thedetermined brightness of the portions corresponding to the elementregion can further be carried out easily.

[0612] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is formed bysubstantially providing a plurality of element shielding layers outsideof the luminescent layer. and wherein the light from the luminescentlayer is emitted through the element shielding layers.

[0613] In this way, element shielding layers made of an easy-to-formmaterial can be formed by using the shielding layers with not manyrestrictions exist on its material as the element region. As aconsequence, the shape of the element region can be formed easily andaccurately.

[0614] The surface light-emitting device according to the presentinvention is characterized in that, the element regions are formed sothat a maximum width thereof is one of a range of 10 through 100nano-meters and another range of equal to or less said range.

[0615] In this way, element regions very narrow in width can berealized. The light directivity of lights after passing throughholograms receives much influence of both the conditions of the lightsbefore passing therethrough and the width of each of the element regionscomposing the hologram layer. However, not much influence is expected onthe conditions of the lights before passing therethrough if the width ofeach of the element regions is in narrow.

[0616] As a consequence, it is considered that the light directivity canbe controlled regardless of the conditions of the lights before passingthrough the hologram layer if the hologram layer is formed with theelement regions very narrow in width. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0617] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0618] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0619] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0620] The surface light-emitting device according to the presentinvention is characterized in that, a hologram layer formedsubstantially corresponding to a pattern of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path,

[0621] and wherein more than one pattern of interference fringes areprepared and light corresponding to one of patterns selected is emittedthrough the predetermined optical path.

[0622] In this way, the surface light-emitting device alone can playboth roles as the light source and the optical elements by making thepatterns of interference fringes of holograms with the hologram patternsof optical elements such as lens, for example.

[0623] Further, the surface light-emitting device can a play role forvarying positions between the light source and the optical element aswell as playing another role for modifications of the light sourceand/or the optical element in the embodiment described above, thesurface light-emitting device being designed capable of selecting apattern of fringe out of more than one patterns.

[0624] As a consequence, those adjustments can be performed withoutcarrying out mechanical movement.

[0625] In other words, a lightweight, compact-profile, and reasonableprice optical-input/output device, yet enables high-speed operation withhigh-durability can be realized with the surface light-emitting device.

[0626] The surface light-emitting device according to the presentinvention is characterized in that, the hologram layer is composed of aplurality of element regions,

[0627] and wherein brightness of portions corresponding to the elementregions is determined in accordance with the pattern of the interferencefringes,

[0628] and wherein the corresponding portions are controlled so as toturn into an ilumination-state corresponding to the determinedbrightness.

[0629] In this way, a surface light-emitting device capable of using avariety of hologram patterns by itself can be manufactured as a resultof carrying out the following steps: 1) forming the element regions in asimple shape used for various purposes, and 2) correspondinglydetermining brightness of the portions corresponding to each of theelement regions to the hologram pattern thus selected. As a consequence,the both roles for varying positions between the light source and theoptical element and for modifications of the light source and/or theoptical element can further be performed with flexibility in the aboveexample.

[0630] The surface light-emitting device according to the presentinvention is characterized in that, at least one of the element regionshas a part substantially formed in circular arc shape.

[0631] In this way, a surface light-emitting device capable of realizingbeams having various modes such as different focal points and/orradiating direction by itself can be manufactured by correspondinglydetermining brightness of the portions corresponding to the elementregions having a part substantially formed in circular arc shape to thepattern of the interference fringes thus selected.

[0632] The surface light-emitting device according to the presentinvention is characterized in that, the element regions aresubstantially disposed in a concentric manner.

[0633] In this way, a surface light-emitting device capable of realizingbeams having various modes such as different focal points by itself canbe manufactured by correspondingly determining brightness of theportions corresponding to the element regions substantially disposed ina concentric manner to the pattern of the interference fringes thusselected.

[0634] The surface light-emitting device according to the presentinvention is characterized in that, a width of the element region is oneof ranges of 10 through 100 nano-meters and another range of equal to orless than said range.

[0635] In this way, element regions very narrow in width can berealized. The light directivity of lights after passing throughholograms receives much influence of both the conditions of the lightsbefore passing therethrough and the width of each of the element regionscomposing the hologram layer. However, not much influence is expected onthe conditions of the lights before passing therethrough if the width ofeach of the element regions is in narrow.

[0636] As a consequence, it is considered that the light directivity canbe controlled regardless of the conditions of the lights before passingthrough the hologram layer if the hologram layer is formed with theelement regions very narrow in width. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0637] The surface light-emitting device according to the presentinvention is characterized in that, the element regions are formed in auniform width, and wherein information containing light intensity of thehologram is reproduced by the brightness of the portions correspondingto the element regions.

[0638] In this way, a hologram layer capable of using various purposescan be formed by making each of the element regions in a fixed width.

[0639] In this case, information containing phase of the holograms maybe reproduced in accordance with positions of the element regionscorresponding to the portions under an illumination-state. As aconsequence, the holograms can be reproduced by varying the brightnessof the portions corresponding to the element regions.

[0640] The surface light-emitting device according to the presentinvention is characterized in that, a plurality of the element regionsare substantially disposed in a matrix manner.

[0641] In this way, a surface light-emitting device capable of usingmore variety of hologram patterns by itself can be manufactured as aresult of using a plurality of the element regions substantiallydisposed in a matrix manner and have more variety of purposes. As aconsequence, the both roles for varying positions between the lightsource and the optical element and for modifications of the light sourceand/or the optical element can further be performed with higherflexibility in the above example.

[0642] The surface light-emitting device according to the presentinvention is characterized in that, the element regions are formed sothat a maximum width thereof is one of a range of 10 through 100nano-meters and another range of equal to or less than said range.

[0643] In this way, element regions very narrow in width can berealized. The light directivity of lights after passing throughholograms receives much influence of both the conditions of the lightsbefore passing therethrough and the width of each of the element regionscomposing the hologram layer. However, not much influence is expected onthe conditions of the lights before passing therethrough if the width ofeach of the element regions is in narrow.

[0644] As a consequence, it is considered that the light directivity canbe controlled regardless of the conditions of the lights before passingthrough the hologram layer if the hologram layer is formed with theelement regions very narrow in width. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0645] The surface light-emitting device according to the presentinvention is characterized in that, information containing lightintensity of the hologram is reproduced by the brightness of theportions corresponding to the element regions.

[0646] In this case, information containing phase of the holograms maybe reproduced in accordance with positions of the element regionscorresponding to the portions under an illumination-state. As aconsequence, the holograms can be reproduced by varying the brightnessof the portions corresponding to the element regions.

[0647] The surface light-emitting device according to the presentinvention is characterized in that, brightness of portions correspondingto the element regions is respectively controlled by adjusting currentvalues flowing through the luminescent layer corresponding to each ofthe element regions.

[0648] In this way, information containing light intensity of theholograms can be reproduced by adjusting the current values.Consequently, reproduction of the holograms can easily be performed.

[0649] The surface light-emitting device according to the presentinvention is characterized in that, the corresponding portions arecontrolled so as to turn into the illumination-state corresponding tothe determined brightness substantially at the same time. Consequently,reproduction of the holograms can be performed with certainty.

[0650] The surface light-emitting device according to the presentinvention is characterized in that, the corresponding portions arecapable of maintaining the illumination-state,

[0651] and wherein the corresponding portions are controlled so as tosequentially turn into the illumination-state corresponding to thedetermined brightness and to maintain the illumination-state.

[0652] In this way, the portions corresponding to the element regionsare simultaneously turned into an illumination-state corresponding tothe determined brightness at the end of scanning for all the lines bysequentially scanning the portions in the luminescent layercorresponding to the element regions. Consequently, reproduction of theholograms can easily be performed with certainty.

[0653] The surface light-emitting device according to the presentinvention is characterized in that, the luminescent layer is made of anorganic material.

[0654] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0655] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0656] The beam generator according to the present invention ischaracterized in that, a beam in a desired form is generated byselecting one of the hologram pattern of the optical element with thesurface light-emitting device.

[0657] In this way, a lightweight, compact-profile, and reasonable pricebeam generator, yet enables high-speed operation with high-durabilitycan be realized.

[0658] The beam generator according to the present invention ischaracterized in that, beams corresponding to a scanning path aregenerated sequentially so as to draw a track thereof along with thescanning path.

[0659] In this way, a lightweight, compact-profile, and reasonable pricebeam scanning device, yet enables high-speed operation withhigh-durability can be realized.

[0660] The plotting device according to the present invention ischaracterized in that, the plotting device carries out plotting with thebeam generator described above, wherein a pattern is plotted with beamscorresponding to the pattern to be plotted which are generated insequential manner.

[0661] In this way, a lightweight, compact-profile, and reasonable priceplotting device, yet enables high-speed operation with high-durabilitycan be realized.

[0662] The light scanning and reading device is characterized in that,the device uses the beam generator. In this way, a lightweight,compact-profile, and reasonable price light scanning and reading device,yet enables high-speed operation with high-durability can be realized.

[0663] The image display device according to the present invention ischaracterized in that, an image display device having a surfacelight-emitting device including a luminescent layer emitting light as aresult of applying a voltage to the electrode and the light beingemitted through a predetermined optical path,

[0664] wherein a hologram layer formed substantially corresponding to apattern of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath,

[0665] and wherein a predetermined holographic image is displayed withthe light from the luminescent layer.

[0666] In this way, visual information can be reproduced inthree-dimensional manner only with the surface light-emitting device ifthe interference fringes of the holograms are formed as hologrampatterns corresponding to visual information such as cubic object(s)and/or character(s). In other words, a lightweight, compact-profile, andreasonable price image display device capable of reproducing visualinformation in three-dimensional manner can be realized.

[0667] The image display device according to the present invention, ischaracterized in that, the hologram layer is composed by forming theelectrode in a shape substantially corresponding to the pattern of theinterference fringes.

[0668] In this way, a shape corresponding to the patterns ofinterference fringes of holograms can be formed easily and accurately byforming the hologram layer with easy-to-form electrodes.

[0669] The image display device according to the present invention ischaracterized in that, the hologram layer is composed by forming theluminescent layer in a shape substantially corresponding to the patternof the interference fringes.

[0670] Light reproduced with high fidelity to the patterns ofinterference fringes may be obtained by utilizing the luminescent layeritself as the hologram layer.

[0671] The image display device according to the present invention ischaracterized in that, the hologram layer is composed by forming ashielding layer in a shape substantially corresponding to the pattern ofthe interference fringes of at a position outside of the luminescentlayer,

[0672] and wherein the light from the luminescent layer is emittedthrough the shielding layer.

[0673] In this way, a hologram layer made of an easy-to-form materialcan be formed by using the shielding layer with not many restrictionsexist on its material as the hologram layer. As a consequence, a shapecorresponding to the patterns of interference fringes of holograms canbe formed easily and accurately.

[0674] The image display device according to the present invention ischaracterized in that, the hologram layer is composed by forming anuneven transparent layer formed unevenly in thickness substantiallycorresponding to the patterns of the interference fringes at a positionoutside of the luminescent layer,

[0675] and wherein the light from the luminescent layer is emittedthrough the uneven transparent layer.

[0676] In this way, a hologram layer made of an easy-to-form materialcan be formed by using the uneven transparent layer with not manyrestrictions exist on its material as the hologram layer. As aconsequence, a shape corresponding to the patterns of interferencefringes of holograms can be formed easily and accurately.

[0677] The image display device according to the present invention ischaracterized in that, the light from the luminescent layer directed toother than the predetermined optical path is emitted to a directionother than the predetermined optical path.

[0678] As a consequence, localization of an imaginary light sourcecreated by reflection of the lights directed to other than thepredetermined optical path can be avoided. Consequently, the lightsource can keep its substantial optical depth narrow. It is, therefor,possible to obtain the lights suitable for reproduction of holograms.

[0679] The image display device according to the present invention ischaracterized in that, the light from the luminescent layer directed toother than the predetermined optical path is reflected and incorporatedwith another light from the luminescent layer directed to thepredetermined optical path so as to intensify the resulting light.

[0680] In this way, the light incorporated can be obtained. It is,therefor, possible to obtain the lights suitable for reproduction ofholograms.

[0681] The image display device according to the present invention ischaracterized in that, the light generated by the luminescent layer isemitted after carrying out resonation of the light.

[0682] In this way, light much like monochromatic radiation having ahigh intensity effectively can be obtained. Also, light having a highdirectivity can be obtained with the device as well. Lights havingsimilar phase can further be obtained. Consequently, it is possible toobtain the lights suitable for reproduction of holograms.

[0683] The image display device according to the present invention ischaracterized in that, the hologram layer is formed alone with a patternlocated periphery of the interference fringes.

[0684] In this way, the hologram layer can be formed with only the partwhere is narrow in distance between the fringes. The directivity oflights after passing through the holograms receives much influence ofboth the conditions of the lights before passing therethrough and thedistance between the fringes. However, more influence of the distancethan that of the condition of the lights before passing through thehologram layer may be expected at the part where is narrow in distance.

[0685] As a consequence, it is assumed that the light directivity can becontrolled in accordance with the distance of the fringes regardless ofthe conditions of the lights before passing through the hologram layerif the hologram layer is formed with the part where is narrow indistance between the fringes alone. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0686] The image display device according to the present invention ischaracterized in that, the hologram layer includes a light-pattern and adark-pattern,

[0687] and wherein a width of the light-pattern is substantially formedin one of a range of wavelength of the light and less than said range.

[0688] In this way, the light-pattern very narrow in width can berealized. The light directivity of lights after passing throughholograms receives much influence of both the conditions of the lightsbefore passing therethrough and the width of each of the light-pattern.However, not much influence is expected on the conditions of the lightsbefore passing therethrough if the width of each of the light-pattern isin narrow.

[0689] As a consequence, it is considered that the light directivity canbe controlled regardless of the conditions of the lights before passingthrough the hologram layer if the hologram layer is formed so as tonarrow the width of the light-pattern. In other words, a hologram layermuch suitable for reproduction of holograms may be realized.

[0690] The image display device according to the present invention ischaracterized in that, the hologram layer includes a light-pattern and adark-pattern,

[0691] and wherein the light-pattern is formed in a fixed width,

[0692] and wherein information containing light intensity of thehologram is reproduced by the brightness of portions generating lightwhere corresponding to the light-pattern.

[0693] In this case, information containing phase of the holograms maybe reproduced by allocating pattern elements having the fixed width. Asa consequence, the hologram layer can be formed by just allocating eachof the element regions having the fixed width. In other words, formationof the hologram layer may easily be carried out.

[0694] The image display device according to the present invention ischaracterized in that, a plurality of element regions are included inthe hologram layer,

[0695] and wherein brightness of portions corresponding to the elementregions is determined in accordance with the pattern of interferencefringes,

[0696] and wherein the corresponding portions are controlled so as toturn into an illumination-state corresponding to the determinedbrightness substantially at the same time.

[0697] In this way, reproduction of the holograms can be performed withcertainty because the portions corresponding to the element regions arecontrolled so as to turn into an illumination-state corresponding to thedetermined brightness substantially at the same time.

[0698] In addition, the element regions may be formed in a simple shape,and information containing light intensity of the holograms can bereproduced in accordance with the brightness of the element regionsbecause the hologram layer includes a plurality of element regions andthe brightness of portions corresponding to the element regions isdetermined in accordance with the patterns of the interference fringes.By forming the display device in this way, information containing phaseof the holograms may be reproduced by allocating pattern elements.Consequently, formation of the hologram may easily be carried out.

[0699] The image display device according to the present invention ischaracterized in that, more than one pattern of interference fringes areprepared and light corresponding to one of patterns selected is emittedthrough the predetermined optical path.

[0700] In this way, a variety of visual informations can be reproducedin three-dimensional manner if the interference fringes of the hologramsare formed as hologram patterns corresponding to visual information suchas several kinds of objects and/or characters. As a consequence an imagedisplay device capable of utilizing in various purposes can be realized.In addition, images can be reproduced dynamic manner by using theseveral kinds of hologram patterns.

[0701] The image display device according to the present invention ischaracterized in that, the luminescent layer is made of an organicmaterial.

[0702] The use of organic materials to the luminescent layer permits theformation thereof with a very thin in thickness in comparison withwavelength of the emitted light therefrom. In this way, the activethickness of the portions emitting light in the luminescent layer can beformed in a thickness, which is negligible in comparison with thewavelength of the emitted light. In addition, the minimum planardimension of the luminescent layer can dramatically be smaller incomparison with the wavelength of the emitted light. It is, therefor,possible to provide a luminescent layer suitable for reproduction ofholograms by using organic materials therefor.

[0703] A lightweight, compact-profile optical-input/output device withreasonable price capable of emitting light can further be realizedeasily because the device can be operated at a low DC voltage.

[0704] The IC card according to the present invention is characterizedin that, the IC card uses the image display device. In this way, alightweight, compact-profile with reasonable price IC card capable ofreproducing visual information in three-dimensional manner can berealized. With the IC card, a higher advertising-effect and difficultiesin forgery can be expected because visual information is reproduced inthree-dimensional manner.

[0705] The surface light-emitting device, the beam generator, the devicefor monitoring reflected light, the plotting device, the light scanningand reading device, the image display device and the IC card accordingto the present invention are characterized in that, the light generatedby the luminescent layer is emitted in a direction substantiallyperpendicular to the luminescent layer as a laser beam after carryingout resonation of the light.

[0706] In this way, it is possible to realize a surface light-emittingdevice much suitable for reproduction of holograms by using the emittedlaser beams. Moreover, a desired illumination pattern may easily beobtained by emitting the laser beam in the direction perpendicular tothe luminescent layer. Consequently, a desired hologram pattern caneasily be obtained.

[0707] The surface light-emitting device, the beam generator, the devicefor monitoring reflected light, the plotting device, the light scanningand reading device, the image display device and the IC card accordingto the present invention are characterized in that, a luminescent layerformed as a multiple semiconductor layer in which a first semiconductorlayer of first conductive type and a second semiconductor layer ofsecond conductive type are substantially connected with each other, andwherein the light generated adjacent of the connection is emitted in adirection substantially perpendicular to the luminescent layer as alaser beam after carrying out resonation of the light.

[0708] In this way, it is possible to realize a surface light-emittingdevice much suitable for reproduction of holograms by using the emittedlaser beams. Moreover, a desired illumination pattern may easily beobtained by emitting the laser beam in the direction perpendicular tothe luminescent layer. Consequently, a desired hologram pattern caneasily be obtained. Further, laser oscillation can easily be performedby employing a semi-conducting substance having a high heat resistancefor the luminescent layer.

[0709] The surface light-emitting device, the beam generator, the devicefor monitoring reflected light, the plotting device, the light scanningand reading device, the image display device and the IC card accordingto the present invention are characterized in that, a plurality ofreflecting mirrors, each having a reflective plane substantiallyparallel to the luminescent layer, is provided at positions so as tointerpose the luminescent layer,

[0710] and wherein the mirrors resonate the light generated by theluminescent layer in a direction substantially perpendicular to theluminescent layer.

[0711] In this way, the volume of areas interposed between the mirrorscan be reduced. As a consequence, the threshold value for initiating thelaser oscillation can be lowered. In other words, a surfacelight-emitting device and the like with low-power consumption can berealized. Further, the hologram layer can further be patterned indetail. In other words, hologram pattern with finer patterning mayeasily be obtained.

[0712] While the embodiments of the present invention, as disclosedherein, constitute preferred forms, it is to be understood that eachterm was used as illustrative and not restrictive, and can be changedwithin the scope of the claims without departing from the scope andspirit of the invention.

What is claimed is:
 1. A surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode, wherein theelectrode is substantially formed in a shape corresponding to a patternof interference fringes of a hologram.
 2. The surface light-emittingdevice according to claim 1, wherein the electrode is composed of a pairof electrode layers interposing the luminescent layer therebetween, andwherein one of the electrode layers is formed as a transparent electrodelayer substantially having the shape corresponding to the pattern ofinterference fringes of the hologram, and wherein the light from theluminescent layer is emitted through said transparent electrode.
 3. Thesurface light-emitting device according to claim 2, wherein a supportingmember is provided to a position outside of the other one of theelectrode layers, and wherein the light from the luminescent layer isemitted through said one electrode layer.
 4. The surface light-emittingdevice according to claim 2, wherein a supporting member havingtransparency is provided to a position outside of said one electrodelayer, and wherein the light from the luminescent layer is emittedthrough said one electrode layer and the supporting member.
 5. Thesurface light-emitting device according to claim 1, wherein theelectrode is composed of a pair of electrode layers interposing theluminescent layer therebetween, and wherein one of the electrode layersis formed in a shape substantially corresponding to a pattern ofinterference fringes of a hologram while forming the other one of theelectrode layers as a transparent electrode layer, and wherein lightfrom the luminescent layer is emitted through the other electrode layer.6. The surface light-emitting device according to claim 5, wherein asupporting member having transparency is provided to a position outsideof the other electrode layer, and wherein the light from the luminescentlayer is emitted through the other electrode layer and the supportingmember.
 7. A surface light-emitting device including a luminescent layerand an electrode, the luminescent layer emitting light as a result ofapplying a voltage to the electrode, wherein a shielding layer formed ina shape substantially corresponding to a pattern of interference fringesof a hologram is provided at a position outside of the luminescentlayer, and wherein the light from the luminescent layer is emittedthrough the shielding layer.
 8. The surface light-emitting deviceaccording to claim 7, wherein the electrode is composed of a pair ofelectrode layers interposing the luminescent layer therebetween, andwherein one of the electrode layers is formed as a transparent electrodelayer while providing the shielding layer at a position outside of saidone electrode layer.
 9. The surface light-emitting device according toclaim 8, wherein a supporting member having transparency is provided toa position outside of the shielding layer, and wherein the light fromthe luminescent layer is emitted through said one electrode layer, theshielding layer and the supporting member.
 10. A surface light-emittingdevice including a luminescent layer and an electrode, the luminescentlayer emitting light as a result of applying a voltage to the electrode,wherein an uneven transparent layer formed unevenly in thicknesscorresponding to a pattern of interference fringes, is disposed at aposition outside of the luminescent layer, and wherein the light fromthe luminescent layer is emitted through the uneven transparent layer.11. The surface light-emitting device according to claim 10, wherein theelectrode is composed of a pair of electrode layers interposing theluminescent layer therebetween, and wherein one of the electrode layersis formed as a transparent electrode layer while providing the uneventransparent layer at a position outside of said one electrode layer. 12.The surface light-emitting device according to claim 11, wherein theuneven transparent layer is a supporting member having transparency, andwherein the light from the luminescent layer is emitted through said oneelectrode layer and the supporting member.
 13. The surfacelight-emitting device according to claim 11, wherein the uneventransparent layer is a passivation layer having transparency, andwherein the light from the luminescent layer is emitted through said oneelectrode layer and the passivation layer.
 14. The surfacelight-emitting device according to claim 1, wherein the light generatedby the luminescent layer is emitted in a direction substantiallyperpendicular to the luminescent layer as a laser beam after carryingout resonation of the light.
 15. A surface light-emitting deviceincluding a luminescent layer and an electrode, the luminescent layeremitting light as a result of applying a voltage to the electrode andthe light being emitted in a direction substantially perpendicular tothe luminescent layer through a predetermined optical path as a laserbeam after carrying out resonation of the emitted light, wherein ahologram layer formed substantially corresponding to a pattern ofinterference fringes of a hologram is formed as a layer one of relatedto light emission and provided on the predetermined optical path. 16.The surface light-emitting device according to claim 14, the devicecomprising: a plurality of reflecting mirrors, each having a reflectiveplane substantially parallel to the luminescent layer, provided atpositions interposing the luminescent layer, wherein the reflectingmirrors resonate the light generated by the luminescent layer in adirection substantially perpendicular to the luminescent layer.
 17. Thesurface light-emitting device according to claim 1, wherein the patternof the interference fringes is formed as a hologram pattern of anoptical element.
 18. A beam generator for generating a predeterminedbeam with the surface light-emitting device defined in claim
 17. 19. Asurface light-emitting device including a luminescent layer and anelectrode, the luminescent layer emitting light as a result of applyinga voltage to the electrode and the light being emitted through apredetermined optical path, wherein a hologram layer formedsubstantially corresponding to the patterns of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path, and wherein the light fromthe luminescent layer directed to other than the predetermined opticalpath is emitted to a direction other than the predetermined opticalpath.
 20. The surface light-emitting device according to claim 19,wherein the electrode is composed of a pair of electrode layersinterposing the luminescent layer therebetween, and wherein both theelectrode layers are formed as transparent electrode layers.
 21. Asurface light-emitting device including a luminescent layer and anelectrode, the luminescent layer emitting light as a result of applyinga voltage to the electrode and the light being emitted through apredetermined optical path, wherein a hologram layer formedsubstantially corresponding to a pattern of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path, and wherein the light fromthe luminescent layer directed to other than the predetermined opticalpath is reflected and incorporated with another light from theluminescent layer directed to the predetermined optical path so as tointensify a resulting light.
 22. The surface light-emitting deviceaccording to claim 21, wherein the electrode is composed of a pair ofelectrode layers interposing the luminescent layer therebetween, andwherein one of the electrode layers is formed as a transparent electrodelayer while forming the other one of electrode layers as an electrodecapable of reflecting light on its surface, and wherein the light fromthe luminescent layer that is directed to said one electric layer andthe light reflected on the surface of the other electrode layer isincorporated and emitted.
 23. The surface light-emitting deviceaccording to claim 22, wherein an optical distance u1 from a luminescentpart of the luminescent layer to the surface of the other electrodelayer is defined as the following equation; u1≈(2n−1)λ/4 wherein “n” isa positive integer, and “λ” represents to a wavelength of a desiredlight emitted from the device.
 24. A surface light-emitting deviceincluding a luminescent layer and an electrode, the luminescent layeremitting light as a result of applying a voltage to the electrode andthe light being emitted through a predetermined optical path, wherein ahologram layer formed substantially corresponding to a pattern ofinterference fringes of a hologram is formed as a layer one of relatedto light emission and provided on the predetermined optical path, andwherein the light from the luminescent layer is resonated and emitted.25. The surface light-emitting device according to claim 24, wherein theelectrode is composed of a pair of electrode layers interposing theluminescent layer therebetween, and wherein one of the electrode layersis formed as a transparent electrode layer while forming the other oneof electrode layers as an electrode capable of reflecting light on itssurface, and wherein dielectric reflective layer not less than one isprovided to a position outside of said one electrode layer, and whereinthe light is resonated between the surface of the other electrode layerand a reflective plane of the dielectric reflective layer, and is thenemitted therefrom.
 26. The surface light-emitting device according toclaim 25, wherein an optical distance u2 from the reflective plane ofthe dielectric reflective layer to the surface of the other electrodelayer is defined as the following equation; U2≈nλ/2 wherein “λ”represents a wavelength of a desired light emitted from the device. 27.The surface light-emitting device according to claim 19, wherein thelight generated by the luminescent layer is emitted in a directionsubstantially perpendicular to the luminescent layer as a laser beamafter carrying out resonation of the light.
 28. A surface light-emittingdevice including a luminescent layer and an electrode, the luminescentlayer emitting light as a result of applying a voltage to the electrodeand the light being emitted through a predetermined optical path,wherein a hologram layer formed substantially corresponding to thepatterns of interference fringes of a hologram is formed as a layer oneof related to light emission and provided on the predetermined opticalpath, and wherein the hologram layer is formed alone with a part locatedperiphery of interference fringes of the hologram.
 29. A surfacelight-emitting device including a luminescent layer and an electrode,the luminescent layer emitting light as a result of applying a voltageto the electrode and the light being emitted through a predeterminedoptical path, wherein a hologram layer formed substantiallycorresponding to a pattern of interference fringes of a hologram isformed as a layer one of related to light emission and provided on thepredetermined optical path, and wherein the hologram layer includes alight-pattern and a dark-pattern, and wherein a width of thelight-pattern is substantially formed in a range of a wavelength of thelight or less than said range.
 30. The surface light-emitting deviceaccording to claim 29, wherein the hologram layer is formed alone with apart located periphery of interference fringes of the hologram.
 31. Thesurface light-emitting device according to claim 28, wherein thehologram layer is composed by forming the electrode in a shapesubstantially correspond to the pattern of the interference fringes. 32.The surface light-emitting device according to claim 28, wherein thehologram layer is composed by forming the luminescent layer in a shapesubstantially correspond to the pattern of the interference fringes. 33.The surface light-emitting device according to claim 28, wherein thehologram layer is composed by forming a shielding layer in a shapesubstantially correspond to the pattern of the interference fringes at aposition outside of the luminescent layer, and wherein the light fromthe luminescent layer is emitted through the shielding layer.
 34. Thesurface light-emitting device according to claim 28, wherein thehologram layer is composed by forming an uneven transparent layer formedunevenly in thickness substantially corresponding to the pattern of theinterference fringes at a position outside of the luminescent layer, andwherein the light from the luminescent layer is emitted through theuneven transparent layer.
 35. The surface light-emitting deviceaccording to claim 28, wherein the light generated by the luminescentlayer is emitted in a direction substantially perpendicular to theluminescent layer as a laser beam after carrying out resonation of thelight.
 36. The surface light-emitting device according to claim 28, thepattern of the interference fringes of holograms is formed as a hologrampattern of an optical element.
 37. A beam generator for generating apredetermined beam with the surface light-emitting device defined inclaim
 36. 38. A surface light-emitting device including a luminescentlayer and an electrode, the luminescent layer emitting light as a resultof applying a voltage to the electrode and the light being emittedthrough a predetermined optical path, wherein a hologram layer formedsubstantially corresponding to the pattern of the interference is formedas a layer one of related to light emission and provided on thepredetermined optical path, and wherein the hologram layer includes alight-pattern and a dark-pattern, and wherein the light-pattern isformed in a fixed width, and wherein information containing lightintensity of the holograms is reproduced in accordance with brightnessof a portion generating light where corresponding to the light-pattern.39. The surface light-emitting device according to claim 38, wherein thehologram layer is composed by forming the electrode in a shapesubstantially correspond to the pattern of the interference fringes. 40.The surface light-emitting device according to claim 38, wherein thehologram layer is composed by forming the luminescent layer in a shapesubstantially correspond to the pattern of the interference fringes. 41.The surface light-emitting device according to claim 39, whereinbrightness of the portion where corresponding to the light-pattern iscontrolled by adjusting a current value flowing through the luminescentlayer.
 42. The surface light-emitting device according to claim 38,wherein the hologram layer is composed by providing a shielding layerformed in a shape substantially corresponding to a pattern ofinterference fringes of a hologram at a position outside of theluminescent layer, and wherein the light from the luminescent layer isemitted through the shielding layer.
 43. The surface light-emittingdevice according to claim 38, wherein the light-pattern is substantiallyformed in a width, a range of which is one of wavelength of the light orless than said range.
 44. The surface light-emitting device according toclaim 38, wherein the light generated by the luminescent layer isemitted in a direction substantially perpendicular to the luminescentlayer as a laser beam after carrying out resonation of the light. 45.The surface light-emitting device according to claim 38, wherein thepattern of the interference fringes is formed as a hologram pattern ofan optical element.
 46. A beam generator for generating a predeterminedbeam with the surface light-emitting device defined in claim
 45. 47. Asurface light-emitting device including a luminescent layer and anelectrode, the luminescent layer emitting light as a result of applyinga voltage to the electrode and the light being emitted through apredetermined optical path, wherein a hologram layer formedsubstantially corresponding to a pattern of interference fringes of ahologram is formed as a layer one of related to light emission andprovided on the predetermined optical path, and wherein the device isfabricated so that the light once emitted through the optical pathreturns through the hologram layer as a reflected light.
 48. The surfacelight-emitting device according to claim 47, wherein the hologram layerincludes a light-pattern and a dark-pattern, and wherein a portiongenerating light where corresponding to the light-pattern is formed sothat light travels in a forward-direction to the optical path but notproceeds in a backward-direction thereto, and wherein a portion notgenerating light where corresponding to the dark-pattern is formed sothat light proceeds in a backward-direction to the optical path.
 49. Thesurface light-emitting device according to claim 48, wherein theelectrode is the hologram layer.
 50. The surface light-emitting deviceaccording to claim 49, wherein the electrode is composed of a pair ofelectrode layers interposing the luminescent layer therebetween, andwherein one of the electrode layers disposed at a position behind theoptical path is formed as the hologram layer, and wherein the other oneof electrode layers disposed at a position in front of the optical pathis formed as a transparent electrode.
 51. The surface light-emittingdevice according to claim 48, wherein the luminescent layer is thehologram layer.
 52. The surface light-emitting device according to claim51, wherein the electrode is composed of a pair of electrode layersinterposing the luminescent layer therebetween, and wherein one of theelectrode layers disposed at a position in front of the optical path isformed as a transparent electrode.
 53. The surface light-emitting deviceaccording to claim 50, wherein a non-light transmission layer formed ina shape corresponding to the light-pattern, is disposed at a positionback-side of said one electrode layer situated behind the optical path.54. The surface light-emitting device according to claim 47, wherein thelight generated by the luminescent layer is emitted in a directionsubstantially perpendicular to the luminescent layer as a laser beamafter carrying out resonation of the light.
 55. The surfacelight-emitting device according to claim 47, wherein the pattern of theinterference fringes is formed as a hologram pattern of an opticalelement.
 56. A device for monitoring reflected light using the devicedefined in claim 55, wherein an optical sensor is disposed at a positionbehind the hologram layer.
 57. A surface light-emitting device includinga luminescent layer and an electrode, the luminescent layer emittinglight as a result of applying a voltage to the electrode and the lightbeing emitted through a predetermined optical path, wherein a hologramlayer formed substantially corresponding to a patterns of interferencefringes of a hologram is formed as a layer one of related to lightemission and provided on the predetermined optical path, and wherein aplurality of element regions are included in the hologram layer, andwherein brightness of portions corresponding to the element regions isdetermined in accordance with the patterns of the interference fringes,and wherein the corresponding portions are controlled so as to turn intoan illumination-state corresponding to the determined brightnesssubstantially at the same time.
 58. The surface light-emitting deviceaccording to claim 57, wherein the corresponding portions are capable ofmaintaining the illumination-state, and wherein the correspondingportions are controlled so as to sequentially turn into theillumination-state corresponding to the determined brightness and tomaintain the illumination-state.
 59. The surface light-emitting deviceaccording to claim 57, wherein the hologram layer is composed by formingthe electrode with element electrodes substantially forming saidpluralities of element regions.
 60. The surface light-emitting deviceaccording to claim 57, wherein the hologram layer is composed by formingthe luminescent layer with element luminescent layers substantiallyforming said pluralities of element regions.
 61. The surfacelight-emitting device according to claim 59, wherein brightness ofportions corresponding to the element regions is respectively controlledby adjusting current values flowing through the luminescent layercorresponding to each of the element regions.
 62. The surfacelight-emitting device according to claim 61, wherein a storing part forstoring current values flowing through the luminescent layer whichcorrespond to each of the element regions respectively, is provided. 63.The surface light-emitting device according to claim 57, wherein thehologram layer is formed by substantially providing a plurality ofelement shielding layers outside of the luminescent layer. and whereinthe light from the luminescent layer is emitted through the elementshielding layers.
 64. The surface light-emitting device according toclaim 57, wherein the element regions are formed so that a maximum widththereof is one of a range of 10 through 100 nano-meters and anotherrange of equal to or less said range.
 65. The surface light-emittingdevice according to claim 57, wherein the light generated by theluminescent layer is emitted in a direction substantially perpendicularto the luminescent layer as a laser beam after carrying out resonationof the light.
 66. A surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path, wherein a hologram layerformed substantially corresponding to a pattern of interference fringesof a hologram is formed as a layer one of related to light emission andprovided on the predetermined optical path, and wherein more than onepattern of interference fringes are prepared and light corresponding toone of patterns selected is emitted through the predetermined opticalpath.
 67. The surface light-emitting device according to claim 66,wherein the hologram layer is composed of a plurality of elementregions, and wherein brightness of portions corresponding to the elementregions is determined in accordance with the pattern of the interferencefringes, and wherein the corresponding portions are controlled so as toturn into an illumination-state corresponding to the determinedbrightness.
 68. The surface light-emitting device according to claim 67,wherein at least one of the element regions has a part substantiallyformed in circular arc shape.
 69. The surface light-emitting deviceaccording to claim 68, wherein the element regions are substantiallydisposed in a concentric manner.
 70. The surface light-emitting deviceaccording to claim 68, wherein a width of the element region is one ofranges of 10 through 100 nano-meters and another range of equal to orless than said range.
 71. The surface light-emitting device according toclaim 68, wherein the element regions are formed in a uniform width, andwherein information containing light intensity of the hologram isreproduced by the brightness of the portions corresponding to theelement regions.
 72. The surface light-emitting device according toclaim 67, wherein a plurality of the element regions are substantiallydisposed in a matrix manner.
 73. The surface light-emitting deviceaccording to claim 72, wherein the element regions are formed so that amaximum width thereof is one of a range of 10 through 100 nano-metersand another range of equal to or less than said range.
 74. The surfacelight-emitting device according to claim 72, wherein informationcontaining light intensity of the hologram is reproduced by thebrightness of the portions corresponding to the element regions.
 75. Thesurface light-emitting device according to claim 67, wherein brightnessof portions corresponding to the element regions is respectivelycontrolled by adjusting current values flowing through the luminescentlayer corresponding to each of the element regions.
 76. The surfacelight-emitting device according to claim 67, wherein the correspondingportions are controlled so as to turn into the illumination-statecorresponding to the determined brightness substantially at the sametime.
 77. The surface light-emitting device according to claim 76,wherein the corresponding portions are capable of maintaining theillumination-state, and wherein the corresponding portions arecontrolled so as to sequentially turn into the illumination-statecorresponding to the determined brightness and to maintain theillumination-state.
 78. The surface light-emitting device according toclaim 66, wherein the light generated by the luminescent layer isemitted in a direction substantially perpendicular to the luminescentlayer as a laser beam after carrying out resonation of the light. 79.The surface light-emitting device according to claim 66, wherein thepattern of the interference fringes is formed as a hologram pattern ofan optical element.
 80. A beam generator for generating a beam in adesired form by selecting one of the hologram pattern of the opticalelement with the surface light-emitting device defined in claim
 79. 81.The beam generator according to claim 80, wherein beams corresponding toa scanning path are generated sequentially so as to draw a track thereofalong with the scanning path.
 82. A plotting device for carrying outplotting with the beam generator defined in claim 80, wherein a patternis plotted with beams corresponding to the pattern to be plotted whichare generated in sequential manner. .
 83. A light scanning and readingdevice using the beam generator defined in claim
 81. 84. An imagedisplay device having a surface light-emitting device including aluminescent layer and an electrode, the luminescent layer emitting lightas a result of applying a voltage to the electrode and the light beingemitted through a predetermined optical path, wherein a hologram layerformed substantially corresponding to a pattern of interference fringesof a hologram is formed as a layer one of related to light emission andprovided on the predetermined optical path, and wherein a predeterminedholographic image is displayed with the light from the luminescentlayer.
 85. The image display device according to claim 84, wherein thehologram layer is composed by forming the electrode in a shapesubstantially corresponding to the pattern of the interference fringes.86. The image display device according to claim 84, wherein the hologramlayer is composed by forming the luminescent layer in a shapesubstantially corresponding to the pattern of the interference fringes.87. The image display device according to claim 84, wherein the hologramlayer is composed by forming a shielding layer in a shape substantiallycorresponding to the pattern of the interference fringes of at aposition outside of the luminescent layer, and wherein the light fromthe luminescent layer is emitted through the shielding layer.
 88. Theimage display device according to claim 84, wherein the hologram layeris composed by forming an uneven transparent layer formed unevenly inthickness substantially corresponding to the patterns of theinterference fringes at a position outside of the luminescent layer, andwherein the light from the luminescent layer is emitted through theuneven transparent layer.
 89. The image display device according toclaim 84, wherein the light from the luminescent layer directed to otherthan the predetermined optical path is emitted to a direction other thanthe predetermined optical path.
 90. The image display device accordingto claim 84, wherein the light from the luminescent layer directed toother than the predetermined optical path is reflected and incorporatedwith another light from the luminescent layer directed to thepredetermined optical path so as to intensify the resulting light. 91.The image display device according to claim 84, wherein the lightgenerated by the luminescent layer is emitted after carrying outresonation of the light.
 92. The image display device according to claim84, wherein the hologram layer is formed alone with a pattern locatedperiphery of the interference fringes.
 93. The image display deviceaccording to claim 84, wherein the hologram layer includes alight-pattern and a dark-pattern, and wherein a width of thelight-pattern is substantially formed in one of a range of wavelength ofthe light and less than said range.
 94. The image display deviceaccording to claim 84, wherein the hologram layer includes alight-pattern and a dark-pattern, and wherein the light-pattern isformed in a fixed width, and wherein information containing lightintensity of the hologram is reproduced by the brightness of portionsgenerating light where corresponding to the light-pattern.
 95. The imagedisplay device according to claim 84, wherein a plurality of elementregions are included in the hologram layer, and wherein brightness ofportions corresponding to the element regions is determined inaccordance with the pattern of interference fringes, and wherein thecorresponding portions are controlled so as to turn into anillumination-state corresponding to the determined brightnesssubstantially at the same time.
 96. The image display device accordingto claim 84, wherein more than one pattern of interference fringes areprepared and light corresponding to one of patterns selected is emittedthrough the predetermined optical path.
 97. The image display deviceaccording to claim 84, wherein the light generated by the luminescentlayer is emitted in a direction substantially perpendicular to theluminescent layer as a laser beam after carrying out resonation of thelight.
 98. An IC card using the image display device defined in claim84.
 99. The surface light-emitting device according to claim 7, whereinthe light generated by the luminescent layer is emitted in a directionsubstantially perpendicular to the luminescent layer as a laser beamafter carrying out resonation of the light.
 100. The surfacelight-emitting device according to claim 10, wherein the light generatedby the luminescent layer is emitted in a direction substantiallyperpendicular to the luminescent layer as a laser beam after carryingout resonation of the light.
 101. The surface light-emitting deviceaccording to claim 99, wherein a plurality of reflecting mirrors, eachhaving a reflective plane substantially parallel to the luminescentlayer, is provided at positions so as to interpose the luminescentlayer, and wherein the mirrors resonate the light generated by theluminescent layer in a direction substantially perpendicular to theluminescent layer.
 102. The surface light-emitting device according toclaim 100, wherein a plurality of reflecting mirrors, each having areflective plane substantially parallel to the luminescent layer, isprovided at positions so as to interpose the luminescent layer, andwherein the mirrors resonate the light generated by the luminescentlayer in a direction substantially perpendicular to the luminescentlayer.
 103. The surface light-emitting device according to claim 15,wherein a plurality of reflecting mirrors, each having a reflectiveplane substantially parallel to the luminescent layer, is provided atpositions so as to interpose the luminescent layer, and wherein themirrors resonate the light generated by the luminescent layer in adirection substantially perpendicular to the luminescent layer.
 104. Thesurface light-emitting device according to claim 7, wherein the patternof the interference fringes is formed as a hologram pattern of anoptical element.
 105. The surface light-emitting device according toclaim 10, wherein the pattern of the interference fringes of hologramsis formed as a hologram pattern of an optical element.
 106. The surfacelight-emitting device according to claim 15, wherein the pattern of theinterference fringes of holograms is formed as a hologram pattern of anoptical element.
 107. A beam generator for generating a predeterminedbeam with the surface light-emitting device defined in claim
 104. 108. Abeam generator for generating a predetermined beam using the surfacelight-emitting device defined in claim
 105. 109. Abeam generator forgenerating a predetermined beam using the surface light-emitting devicedefined in claim
 106. 110. The surface light-emitting device accordingto claim 21, wherein the light generated by the luminescent layer isemitted in a direction substantially perpendicular to the luminescentlayer as a laser beam after carrying out resonation of the light. 111.The surface light-emitting device according to claim 24, wherein thelight generated by the luminescent layer is emitted in a directionsubstantially perpendicular to the luminescent layer as a laser beamafter carrying out resonation of the light.
 112. The surfacelight-emitting device according to claim 29, wherein the hologram layeris composed by forming the electrode in a shape substantially correspondto the pattern of the interference fringes.
 113. The surfacelight-emitting device according to claim 29, wherein the hologram layeris composed by forming the luminescent layer in a shape substantiallycorresponding to the pattern of the interference fringes.
 114. Thesurface light-emitting device according to claim 29, wherein thehologram layer is composed by forming a shielding layer in a shapesubstantially corresponding to the patterns of interference fringes ofholograms at a position outside of the luminescent layer, and whereinthe light from the luminescent layer is emitted through the shieldinglayer.
 115. The surface light-emitting device according to claim 29,wherein the light generated by the luminescent layer is emitted in adirection substantially perpendicular to the luminescent layer as alaser beam after carrying out resonation of the light.
 116. The surfacelight-emitting device according to claim 29, wherein the pattern of theinterference fringes is formed as a hologram pattern of an opticalelement.
 117. A beam generator for generating a predetermined beam usingthe surface light-emitting device defined in claim
 116. 118. The surfacelight-emitting device according to claim 40, wherein brightness of theportion where corresponding to the light-pattern is controlled byadjusting a current value flowing through the luminescent layer. 119.The surface light-emitting device according to claim 52, wherein anon-light transmission layer formed in a shape corresponding to thelight-pattern is disposed at a position back-side of said one electrodelayer situated behind the optical path.
 120. The surface light-emittingdevice according to claim 60, wherein brightness of portionscorresponding to the element regions is respectively controlled byadjusting current values flowing through the luminescent layercorresponding to each of the element regions.
 121. The surfacelight-emitting device according to claim 120, wherein a storing part forstoring current values flowing through the luminescent layer whichcorresponding to each of the element regions respectively, is provided.